XX. ELECTRICAL TREATMENT IN CASES OF LEAD POISONING…

XX. ELECTRICAL TREATMENT IN CASES OF LEAD POISONING

The treatment of lead poisoning by electricity is based upon two distinct ideas. First, the use of the electrolytic effects of a current to eliminate the metal from the system; and secondly, the treatment of its symptoms, especially its nervous symptoms, by electricity, in virtue of its usefulness as a remedy for paralytic disorders. In any treatment of lead poisoning these two considerations are of importance:--

1. The Elimination of the Metal.--There is no doubt that the elimination of the metal is necessary for the recovery of a patient from the effects of the poison. In the ordinary course of events elimination probably takes place by the sweat glands of the skin, by the kidneys, and by the mucous membrane and glands of the bowel; whereas the direct effect of an electrolytic elimination would be to cause the lead to pass by a process akin to osmosis in some soluble form, most probably as a chloride of lead, from the tissues of the body to the electrolyte surrounding the body, and so to the plates or poles of the electrolytic cell or bath in which the patient is placed. Unfortunately, the experimental evidence that lead can be extracted from the tissues of the body in this way is not free from possible sources of error. The amount of lead existing in the tissues of a patient suffering from lead poisoning may not be more than a few grains in weight, and the quantity which could be deposited by electrolysis in an electric bath of the ordinary strength and duration could not amount to more than a few milligrammes. In solutions such as the juices of the body, containing but little lead, the lead ions could play but an insignificant part in the transport of the current, and therefore there are considerable difficulties in depositing at the poles of the bath a quantity of lead which could only be a small fraction of the total amount contained in the body. Lead compounds also have a somewhat special behaviour when submitted to electrolytic treatment, for whereas most metals are deposited from their solutions at the negative pole, lead compounds when submitted to electrolysis have a tendency to be deposited in part upon the positive pole, as lead peroxide, and in part upon the negative pole, in a spongy metallic form. In the presence of chlorides the lead peroxide does not adhere to the positive pole, but tends to undergo changes and decomposition. Statements have frequently been made that after the treatment of a patient by electrolysis in a bath of water, traces of lead may be found upon the poles of the bath. I have been able to detect lead on the plates in one case of my own in which the experiment was tried. But there is always some uncertainty as to the source of this lead, for in cases of workmen it may very well have come from dust and dirt containing lead which has been mechanically deposited upon the surface of their skin; or again, it may be lead which has actually come from the tissues, but has already been eliminated by the sweat glands, and is lying on the surface of the skin, so that it could be washed away by ordinary washing with soap and water. But at the same time we must not forget that even if the direct electrolytic elimination of lead is a thing which can be brought about by electricity, it is not the only way in which electrical applications may act favourably in removing lead from the system, for by their means we can also influence what may be called the natural processes of elimination, so that after electrical treatment one might expect to find traces of lead in the urine, in addition to that which might be found by a careful examination of the poles of the bath. And so far as mere opinions go, I certainly take the view that electrical treatment favours such an indirect elimination of the poison, and to that extent is of service in the treatment of cases.

2. The Electrical Treatment of the Paralysis caused by the Lead.--This is probably as important, or more important, than the question of the extraction and elimination of the metal. In practical treatment we may say that it is the paralytic symptoms which are most readily dealt with by electrical methods. All forms of electrical application have been recommended for paralysis due to lead, e.g., the constant current, the interrupted current of the coil, and, more recently, the sinusoidal current of an alternating dynamo. These can all be used, and apparently with advantage. As I have frequently maintained in other places, the state of contractility in a paralysed muscle need not necessarily dictate to us the form that the electrical applications are to take. I mean that when a muscle paralysed from lead ceases to react to induction coil currents, it does not at all follow that induction coil currents are useless in its treatment; and, therefore, I consider that the widely held view that a coil should be used only for those muscles capable of responding to it is not correct. Muscles which show the reaction of degeneration, and contract only to direct applications of the constant current, will almost certainly derive benefit from a course of induction coil currents, and these should in every case be given to them, not to the exclusion of constant currents, but in addition thereto. Many of the rules laid down for the treatment of paralysis by electricity are based upon the view that the therapeutic effect of electricity upon a muscle can be measured by the amount of contraction which the electrical application can produce in it; but this is quite wrong. Even in the absence of all visible contractions in a muscle under treatment, electrical applications produce effects--vasomotor, trophic, and other--which are of service. Indeed, we may go further, and say that treatment by currents purposely made strong, in order to set up contractions in paralysed muscles with very feeble contractility, may easily be overdone, and that fatigue and injury may be caused to muscles through too severe stimulation when strong currents are demanded, in order to make them contract visibly.

In the practical treatment of paralysis due to lead, the choice of an electrical method will turn upon the supposed relative advantages of electrolytic extraction of the metal on the one hand, and of electrical stimulation of the paralysed parts on the other. For the former the electric bath with constant current is to be used, and for the latter induction coil currents or sinusoidal currents, with or without a water bath. The advantages of the sinusoidal current over that of the induction coil consist mainly in the greater smoothness with which the current varies in the former case, and in the greater magnitude of the currents which can be borne. The two methods differ from each other rather in degree than in essence. When, as is usual, the case is one of paralysis of the extensor muscles of the forearm, the use of an arm-bath as the medium for applying the electricity has very decided advantages, so that I am accustomed to treat most of my cases by the arm-bath and sinusoidal current. In cases of severe or extensive lead poisoning, or in cases where the muscles of the lower limbs are affected, I make use of the full-length bath, and at the commencement of the case would advise the use of direct and sinusoidal currents on alternate days, in order to secure electrolytic effects as well as those of simple stimulation. It is probable that hot baths, without electricity, are of very decided service in treating symptoms due to lead. In former days the thermal waters of Bath enjoyed a very considerable reputation in this disease. Thus, by combining a full-length bath with electricity, one is able to make use of the increased elimination set up by hot bathing, as well as of the increased elimination set up by general electrical stimulation. The electrolytic effect also comes in if the current used is a continuous one, but not so if it is alternating. In practical treatment, the cases of lead poisoning most commonly met with, are cases of operatives who handle lead, or some preparation of lead, in the course of earning their living. The symptoms of which they commonly complain in London, at least, are wrist drop and paralysis of the extensors of the wrist and fingers. This is the class of case which I have had under treatment during the last ten years; and the opinion which I have formed of electrical treatment is decidedly favourable. Although in a number of cases the lead has had many years in which to poison the patient, yet it is the rule that within a few weeks from the commencement of electrical applications the paralytic symptoms become very considerably decreased. Unfortunately, recovery is usually followed by a return to the old occupation; fresh infection follows, and paralytic symptoms sooner or later reappear. The patient returns for further treatment under conditions less favourable than before. He is older, the system is more seriously damaged, and his recovery is apt to be less perfect than on the previous occasion. It is this state of things which is chiefly responsible for the fact that brilliant results are not often met with in the treatment of lead poisoning due to occupation. In districts where lead poisoning is common, I would recommend an installation for electrical treatment on the following lines: (1) one or more arm-baths; (2) one or more full-length baths for the whole body. Both of these sets of baths should be supplied with sinusoidal current, generated by a dynamo on the premises, or drawn from the mains of an electric light station, if the current supplied in the neighbourhood should happen to be alternating. In each case some clockwork or other mechanical contrivance for slowly varying the current from zero to the maximum might with advantage be installed, although good results may be obtained without this. In addition, for direct treatment by constant current in special cases, it would be necessary to have a battery or other source of constant current, either for use with the bath or for local applications by means of pads and conductors of the usual class. The induction coil may be used where the sinusoidal current cannot be obtained, but wherever possible, the latter should be used in preference. A pressure of ten or twelve volts is about a suitable one for an arm-bath, and if an average of twelve and a half volts per arm-bath is taken, it is sometimes convenient to arrange the arm-baths in series, as is done, for example, at St Bartholomew’s Hospital, where four arm-baths in a series are fed from one source at fifty volts. This, it will be seen, gives twelve and a half volts per bath, minus a small loss of one volt or so over the whole circuit for the conductors. So if eight or ten baths could be employed with advantage, they might be arranged in a single series upon mains of a hundred volts pressure. In the fitting up of a new establishment, it would be convenient to provide waste pipes and water taps fixed over them, to obviate the inconvenience of filling and emptying by hand. A very convenient vessel for arm-bath treatment is an oblong stoneware picklepan, which can usually be obtained in towns; or wooden vessels of the same shape may be made almost anywhere. It is advantageous to use narrow oblong vessels of a suitable length and width to take the arms and hands, because with round tubs there is considerable loss of current, carried by the water without entering into the patient. There is also a certain waste of hot water by reason of the greater capacity of round tubs. The electrodes for arm-baths may conveniently be made of one piece of sheet copper or sheet zinc, shaped like a tennis racket, with the handle bent over in a hook, by which to suspend it to the end of the tub.

The progress of treatment is slow, and without incident. There is a gradual return of power and a gain in thickness of the wasted muscles. The duration of the case varies much with the severity of the poisoning, and the state of health of the patient. The final results are good.

H. LEWIS JONES.

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XXI. ARSENIC

Arsenic is employed for colouring purposes in various arts and industries, and may produce injurious effects on the workers and on others who are exposed to the influence of the poison. A Committee of the Medical Society of London, of which I was secretary some twenty years ago, compiled from the information collected by them the following list of articles in which arsenical pigments, dyes, and mordants were used.

Paper, fancy and surface coloured, in sheets for covering cardboard boxes; for labels of all kinds; for advertisement cards, playing cards, wrappers for sweetmeats, cosaques, etc.; for the ornamentation of children’s toys; for covering children’s and other books; for lamp shades, paperhangings for walls and other purposes; artificial leaves and flowers; wax ornaments for Christmas trees and other purposes; printed or woven fabrics intended for use as garments; printed or woven fabrics intended for use as curtains or coverings for furniture; children’s toys, particularly inflated indiarubber balls with dry colour inside, painted indiarubber dolls, stands and rockers of rocking-horses and the like, glass balls (hollow); distemper colour for decorative purposes; oil paint for the same; lithographers’ colour printing; decorated tin plates, including painted labels used by butchers and others to advertise the price of provisions; japanned goods generally; Venetian and other blinds; American or leather cloth; printed table baizes; carpets, floorcloth, linoleum, book cloth and fancy bindings. To this list may be added coloured soaps, wafers, sweetmeats, and false malachite. Arsenic is also used in the preparation of skins for stuffing and of some preservatives used by anatomists. Workers employed in the manufacture of any of these things may suffer from the effects of the arsenic contained in the materials which they handle. The fluid known as “sheep dip,” which is sold for the purpose of killing tic on sheep, contains a large quantity of arsenic. Occasionally the men who manufacture the liquid or who wash the workmen’s clothes have suffered from the effects of arsenic upon their extremities and nervous system.

The metal is mostly employed in the form of green arsenites of copper, known as Scheele’s green, and Schweinfurt or Vienna green. The poison gains admission to the system either by being carried into the mouth on the hands and thence taken into the stomach, or by inhalation into the lungs.

In the preparation of artificial flowers Scheele’s green is powdered over the leaves, and in this process some of the dust is drawn in with the breath, while some may lodge in the furrows of the skin and under the nails. In the manufacture of green wallpapers Scheele’s green and the aceto-arsenite of copper are mainly used; from 1 grain of the poisonous substance to 50 or 60 grains per square foot has been found in different samples. Arsenic has been found in red, orange, brown, and grey papers as well as green. The poisonous material may be dusted off the wallpapers and distributed through the atmosphere of the room. Bamberg, of Stockholm detected arsenic in the atmosphere of a room that had been papered for twenty-five or thirty years. According to Parkes and Kenwood,[75] in the case of the smoother papers arseniuretted hydrogen is formed by decomposition of the size and paste acting chemically on the arsenical salt. The same authors point out that even distempered walls must not be assumed to be innocuous, as there is frequently arsenic in distemper which is mixed with size to make it adhere, thus forming a combination of organic matter and arsenic ready for the development of arseniuretted hydrogen.

Persons living in rooms hung with arsenicated wallpapers, and workmen who strip walls or hang pictures, are liable to suffer from the inhalation of the poisonous dust or vapour. Injurious effects may also be caused by the use of green lamp shades, and of gloves, stockings, and other articles of clothing coloured with aniline dyes in the preparation of which arsenic is largely employed. The use of arsenic in many of the arts that have been enumerated, and particularly in the manufacture of wallpapers and in the tinting of textile and silken fabrics intended for furnishing and clothing purposes, also of arsenical colours, has greatly diminished since attention was called to the danger of these by the Medical Society and by sanitarians, among whom the late Mr Henry Carr[76] deserves special mention. Yet, as is proved by cases which are from time to time reported in the papers, they are still too much employed.

Symptoms.--The symptoms are those of chronic arsenical poisoning, and may vary in severity from slight inflammation of the eyes or conjunctivitis, and running at the nose, or coryza, to prostration, or convulsions ending in death. The strong are attacked as well as the weak. In the slighter forms of the affection they are marked by conjunctivitis, running at the nose, and injection, with dryness and soreness of the throat, accompanied by depression. In more severe forms there is headache with colicky pain and abdominal “cramps,” with vomiting, diarrhœa, and sometimes dysentery; the throat and mouth are sore and parched; there is great thirst, with distaste for food. The congested condition of the respiratory passages manifests itself by cough and bronchial catarrh, sometimes by asthma. If the cause is not removed the affection may last indefinitely in a stage of more or less troublesome indisposition, or the prolonged gastro-intestinal derangement may gradually undermine the health and exhaust the patient. In some cases the nervous system suffers most; there is increasing depression, with restlessness and insomnia; in certain severe cases paralysis of the extremities occurs, with convulsions ending in death. This, however, is altogether exceptional, and indeed death from arsenical poisoning of what may be called industrial origin is decidedly rare.

In certain cases arsenic produces local as well as general effects. According to Arlidge[77] workers employed in the manufacture of arsenical green often exhibit peculiar symptoms. That product is derived from arsenite of soda, which is decomposed by sulphate of copper, and the resultant treated with pyroligneous acid.

The workers are liable to the development of boils and pimples, and suffer from an itching eruption about the nostrils and in the flexures of the arms. In severer cases there is headache with thirst and nausea, and an irritating eruption appears on the scrotum. Vomiting, quickening of the pulse, and conjunctival injection are observed in some persons. In workmen employed in the calcining or “burning” houses for arsenical ores the fumes produce sometimes gastric disturbances, sometimes bronchial and laryngeal irritation. The commonest effect is the production of an eruption about the genitals and on the exposed parts of the body, especially at the bends of the limbs. Stockings, handkerchiefs, gloves, etc., dyed with aniline colours often cause severe irritation, especially on the skin of delicate women and children. This ought never to occur, for if the process is rightly carried out no arsenic passes into the finished dye.

Treatment and Prophylaxis.--The first principle of treatment is removal of the cause. The symptoms will then, in the great majority of cases, spontaneously disappear. Debility or other conditions calling for active measures should be treated secundum artem.

As regards the prophylaxis, in trades where exposure to the arsenic is unavoidable, sanitary precautions on the same lines as those taken against lead poisoning should be enforced. For colouring purposes arsenical colours are unnecessary. In the dyeing of textile fabrics and in the tinting of papers they should be absolutely prohibited.

No paper should be placed on a wall unless it be guaranteed free from arsenic, and even with a guarantee from the manufacturer it is advisable to test a piece with Marsh’s apparatus to make sure.

MALCOLM MORRIS.

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XXII. CHINA AND EARTHENWARE MANUFACTURE: POTTERS’ ROT

In all dusty trades pulmonary disease is the cause of death of large numbers of the workpeople. The manufacture of pottery is a dusty trade. Potters’ asthma and consumption have for long been known. The potteries of Staffordshire formerly had an unenviable notoriety on account of the prevalence of ill-health, and the large death-rate among the hands employed. For much that we know of the pulmonary diseases of potters and of pneumoconiosis in general we are indebted to Drs Greenhow, Addison, Peacock, and the late Dr J. T. Arlidge, who, as Physician to the North Staffordshire Infirmary, Stoke-upon-Trent, had unusual opportunities of observing and recording the prevalent diseases of that district.

In the manufacture of china and earthenware the workpeople are exposed to two dangers: (1) pulmonary disease due to inhalation of particles of clay and flint; and (2) plumbism in consequence of the presence of lead used in the glazes and for colouring purposes. In another part of the book the dangers incidental to lead poisoning in potteries are dealt with. Here we are concerned with mineral dust solely, and its effect upon the lungs. Cheap pottery is made from ordinary clay, but in the manufacture of the finer ware, Cornish clay and stone are used. In firing china, ground flint is largely used as a packing between the cups, saucers, and plates, etc., when these are placed in the “saggers” or burnt-clay boxes in the ovens. In addition to the ingredients mentioned above, ground calcined bone is also one of the constituents of china.

Clay and flint both contain very hard, sharp, angular particles of silex, which when drawn into the respiratory organs during inhalation are not dissolved by the secretions of the bronchi. They become deposited in the smallest bronchial tubes and the pulmonary alveoli, and set up irritation. The initial process in the manufacture of earthenware consists in mixing the clays with ground flints and water. This is rather a dusty operation, but fortunately only a few men are employed at it. When properly mixed, the compound is known as “slip,” and the men are called slip-makers. The mixing of the slip is sometimes done by hand by means of long, broad pieces of wood, but usually by machinery. The next stage in the manufacture is known as “throwing,” where the potter throws moist clay upon a revolving wheel, and by means of his hands and fingers shapes the clay into all forms of useful dishes, elegant vases, etc. These products are known as hollow ware, but other kinds of ware just as useful, e.g. plates and saucers, can be made by pressing. The clay vessel when removed from the potter’s wheel is felt by the fingers when run over it to be rough and uneven, and in order to get the required smoothness it is necessary later on to turn such hollow ware as cups upon a lathe, while flat goods like plates and saucers are made even by being rubbed with tow or flannel upon a rapidly revolving table. This process is called “towing.” Ware thus smoothed is ready for the oven. The first firing is known in the trade as “biscuiting.” After this it is ready to be painted or imprinted by coloured transfers, and then glazed. The ware to be fired is placed in large thick-walled vessels the size of an ordinary cheese, made of very coarse local clay, and known by the name of “saggers.” These are capable of withstanding great heat. Into these the earthenware and china goods are packed, care being taken to separate the individual china pieces from each other by plenty of loose ground flint. The men who carry the saggers into the kilns are called “placers.” They build up the saggers on the top of one another, pile after pile, and when doing this they are naturally exposed to alternating heat and cold, to high temperatures in ovens just emptied, to the fumes of sulphur in the kilns from the expiring fires, and to a considerable amount of dust when emptying the saggers. Coming out of the warm kilns covered with perspiration they run the risk of getting chilled.

In this description of the manufacture we have simply dealt with ware that has not been glazed or in any way brought into contact with poisonous compounds, such as lead. The products have only once been fired. Should the biscuited ware be subsequently glazed, this is done by dipping it into a liquid which contains, among other things, “raw” or “fritted” lead. The man who plunges the ware into the glaze is called a “dipper,” and he is followed in his work by the dipper’s cleaners, who rub the rough edges off the ware, while the person who places the dipped ware in the saggers, which go again into the oven for a second firing, is called a “glost placer.” The workman who fills the unglazed ware in the saggers and carries them into the kilns for the first firing is, as already stated, called a “placer.” He only incurs such risks to health as might be caused by exposure to varying temperatures and to dust, but the “glost placer” runs in addition the risk of lead poisoning. About 3 per cent. of them suffer from plumbism.

Since, however, we are only concerned at present with dust and its effect upon the respiratory organs, we shall adhere to a description of those processes in potteries in which it prevails, and of these the two that are the dustiest and the most dangerous are “towing” or smoothing of the ware before it has been fired, also what is known as the “scouring” or cleaning of china after it has been biscuited. The scouring of china is generally done by women, sometimes by hand, by brushing the ware over a wooden trough so that the ground flint can be collected and used over again. The atmosphere of the workroom is often thick with dust, while the hair and clothing of the women are literally white with the fine particles of flint. For dust and danger there is no comparison between the throwing and turning of unfired clay products and the cleaning of china that has been once fired. Unless provision is made by fans for the removal of the dust, the air is so thick that no person could scour china for even a few weeks or months without suffering from bronchial irritation or bronchitis, cough and shortness of breath. Dr Prendergast of Hanley, Staffordshire, informs me that after two months’ work in scouring china, a healthy woman will often present symptoms suggestive of phthisis, but happily the condition of the lung is remediable. Potters’ asthma and consumption, as indeed all forms of lung disease due to dusty occupations, are becoming fortunately fewer and fewer every year in this country, owing to the improved appliances in factories for getting rid of dust. The late Dr Arlidge told me that the chances of obtaining a good illustration of potters’ phthisis as a pathological specimen was becoming increasingly difficult, and the same information has been sent to me from Sheffield as regards steel grinders’ lung.

In addition to visiting the largest potteries in England and Scotland, I have had the opportunity of inspecting many on the Continent, and particularly the porcelain works at Limoges, where I saw something of the baneful effects upon the French potters of the scouring of china. In Limoges the porcelain is made from a very fine white clay or kaolin, which is found in the district. The products made from this kaolin are dipped in a glaze containing felspar and quartz, and whose composition is silica 70, aluminium 17, potash 13.

For more than a century porcelain has been manufactured in Limoges, a town containing 80,000 people, of whom, roughly speaking, 15,000 are engaged in the potteries in the town and neighbourhood, men and women about equally. The kaolin is found at St Yrieix, a village twenty-six miles south of Limoges. There is therefore very little expense incurred in the railway transport of the raw material. Labour, too, is on the whole cheap. In Limoges there are sixteen or seventeen large potteries with almost double that number of smaller workshops. The brushing-off or époussetage of the fired or biscuited ware is done both by women and men by means of soft feather brushes. It is a very dusty operation, and where there are no fans for its removal, as in some of the factories I visited, the air was thick with dust. The windows were open at the time, but currents of air obtained by this means exercised no very appreciable influence upon the dust. It is not this kind of ventilation that is required under these circumstances. In the matter of the provision of artificial means for the removal of dust and the renewal of air in the potteries of Limoges, some of the manufacturers seemed to me to be rather behind than in advance of the owners of large factories in Staffordshire. Accordingly I was not unprepared for the information that among the potters, especially the brushers-off or scourers, in Limoges, the mortality from pulmonary consumption and chest diseases is high. The harmful operations in porcelain works are the emptying of the kilns, the removal of the ware from the saggers, and the brushing of this ware; while the hard dust that rises during the polishing of the all but finished articles is equally dangerous. The polishing has for its object the removal of any roughness from the edges or surfaces of the ware, and it is generally done on a revolving wheel by means of a broken piece of china, the workman using this as the smoothing agent. The men and women employed in these operations are usually well covered with dust, yet it is seldom that they wear respirators. Fans for the removal of the dust were present in only very few of the factories. The employés objected to them on the ground that they created a strong draught of cold air. Dr Raymondaud, one of the Professors in the School of Medicine, Limoges, has made a special study of the diseases of porcelain makers, particularly of pulmonary consumption and chronic bronchitis. He found that the potteries furnished a larger number of patients suffering from lung diseases than did the other trades of the district. Of 75 deaths registered in Limoges as occurring among china makers, 36 were due to phthisis, and of 30 potters whom Raymondaud examined, 20 were suffering from pulmonary consumption. Pulmonary phthisis is regarded as the principal disease affecting the workers in the Limoges potteries.

The discovery of the tubercle bacillus by Koch has tended to unify medical opinion as to the cause of pulmonary phthisis. The bulk of pulmonary phthisis is tubercular and is due to the bacillus. Other conditions, however, are not without their influence, such as hereditary predisposition, constitutional weakness, infection at home, and the effect of chills; but admitting all these, there is considerable evidence in favour of the view that dust plays an important part in producing potters’ phthisis, which, as previously remarked, differs in some respects from tubercular consumption. Dr Lémaistre, with whom I discussed this subject, had analysed the air of the Limoges potteries, and he found that the dust in some of the workshops is composed of earthy particles, fragments of granite, flint, particles of dried glaze, soot, and wood charcoal. The atmosphere which the brushers-off, the finishers, and the porcelain makers generally work in, he found contained 640 million particles of dust to the cubic metre, while several of the finishers, i.e. those persons whose duty it is to remove the excess of dried glaze on the ware, often work in an atmosphere containing 680 million particles to the cubic metre. The particles in the latter instance are smaller than those first mentioned, and they therefore remain a longer time suspended in the air of the workroom. This large number of particles of dust in the air is one explanation of the frequency of bronchitis and of pulmonary disease, and also of the small chalk-like masses found after death in the lungs of porcelain makers, but which must not be confounded with cretaceous tubercles. Whatever may be the influence of the dust-laden atmosphere of a pottery in causing pulmonary fibrosis, the accidental presence of the tubercle bacillus in addition would go far to aggravate existing pulmonary conditions, and tend to transform a non-tubercular affection of the lungs into one of a true specific character. It is thus that the presence of a tuberculous person in a workroom becomes a source of danger to his fellow-workmen. Particles of clay or china dust, when inhaled, can only act mechanically upon the lining of the small bronchial tubes and pulmonary alveoli, but by making a breach upon their epithelial coating they reduce the local vital resistance, and pave the way for the entrance of the tubercle bacilli. Dust, therefore, weakens the lung, and by altering its structure, induces conditions that favour the development of the tubercle bacilli. Apart from bacillary infection, dust is itself a cause of danger: it is capable of inducing bronchitis, and if long inhaled causes fibrosis of the lungs of potters. The pulmonary consumption of porcelain-makers differs from tubercular phthisis in the fact that it is of slower development, and is of longer duration; that it less seldom attacks the young than those of middle life and more advanced age; also that there may be found in the lungs after death calculous concretions, which on chemical examination are found to be composed of carbonate and phosphate of lime, silica, and oxide of iron, with a certain amount of organic matter. The average age at death of men from fibroid phthisis in the potteries of Limoges is forty-three, and of women thirty-eight years. The same symptoms just described as having been observed in the Limoges porcelain-makers are also found in workers in pottery in this country, viz., cough, shortness of breath, and progressive emaciation, but there is a greater tendency to blood-spitting in French porcelain-makers than Arlidge found among the potters in Staffordshire.

Symptoms.--It is not until an individual has worked, as a rule, some months or years at his trade that he shows signs and symptoms of potters’ phthisis. In this, as in other forms of chronic pulmonary disease, there is cough on getting up in the morning, but this circumstance attracts little or no attention, as the general health usually remains good for a lengthened period. At first white and frothy, or speckled from the greyish-black dust that has been inhaled, the expectoration by degrees becomes purulent, while the cough, no longer confined to the morning, becomes more paroxysmal in character, and is attended by shortness of breath, which tends to get worse with time. On examining the chest it is found that the amount of shortness of breath or dyspnœa is out of all proportion to the amount of consolidated lung that may be present. It is a fact well known to every member of the medical profession that tubercular consumption much more frequently affects the apices or uppermost parts of the lungs, i.e. just below the collar-bones, than the lowest portions, a circumstance very largely due to the imperfect inflation or ventilation of those particular regions, so that when they become the seat of catarrh or of subacute inflammation, the morbid products that are secreted and effused are, owing to the limited range of movement of this part of the chest wall, and incomplete aëration of this part of the lungs, with difficulty expectorated. A catarrh therefore tends to linger in the apices of the lungs, and offers opportunities for bacillary infection. In dust diseases of the lungs, on the other hand, it is not the apices that become affected so much as the lower and back parts of the lungs. This is an important distinction between the two, for it shows that a different cause must have been in operation. Limited areas of dulness, indicating small patches of consolidated lung, can be detected here and there in the chest, especially at the base behind or close to the shoulder-blades. In the early stages there is neither the evening rise of temperature, the feverishness, nor the accelerated pulse and rapid loss of flesh which are so pathognomonic of tubercle. Arlidge says there is, too, a wonderful immunity from blood-spitting. If an afflicted workman, therefore, at this stage were to give up his employment and seek for some occupation out-of-doors, the chances are that he would still have a good spell of life before him; but if, on the other hand, he is contented to remain at his occupation, sooner or later he becomes the confirmed victim of potters’ phthisis. His vital resistance becomes gradually more and more enfeebled. His preference for indoor life, daily exposure to infection in the factory, and his overcrowded home, lay the individual open to the chances of a tubercular lesion becoming grafted upon a fibrotic lung. Dr Arlidge found that the mean age at death of male potters aged twenty years and upwards was forty-six and a half years, whilst that of non-potters stood at fifty-four. Dr Prendergast tells me that potters working in dust generally die at the age of forty-five. Among potters Arlidge found as the most frequent causes of death pulmonary consumption, diseases of the heart and nervous system. In the workpeople of the district other than potters, while the death-rate from diseases of the chest was 7.86 per cent., the rate for potters was 12.29. Taking the male population generally and their entire mortality from all causes at the time that Arlidge wrote, we find that the deaths of male potters from diseases of the respiratory organs were 60 instead of 27 per 1000, and that the decennial period from fifty to sixty gave the greatest number of deaths, each preceding decennium back to twenty giving less and less, while the maximum mortality from phthisis as opposed to diseases of the lungs generally was reached between the ages of thirty and forty years. Before the age of forty, therefore, the bulk of the potters who have contracted lung disease, and who have become tubercular, die; whereas in those who contract the disease later on they become less liable to the tubercular type of the malady. Bronchitis is met with among the male pressers who are exposed to the dust of the clay, but in china scourers pulmonary diseases are extremely prevalent; as many as 40 per cent. were found suffering from phthisis and 25 per cent. from bronchitis. As already stated, the phthisis in potters is in the early stages usually not tuberculous. So much so is this considered to be the case that Dr John Tatham,[78] at page xcvii. of Supplement to the Fifty-fifth Annual Report of the Registrar-General of Births, Deaths, etc., Part II., 1897, in speaking of potters (earthenware makers) sustaining a mortality from phthisis and respiratory diseases together far in excess of that experienced by other groups of workers, e.g. 453 as against 100 agriculturists, says that “potters succumb to non-tubercular disease of the lungs more rapidly than they do to phthisis, and it is certain that much of the so-called ‘potters’ phthisis’ ought properly to be designated non-tubercular cirrhosis of the lung.” Cirrhosis is a medical term sometimes used instead of fibrosis.

Prevention.--Ventilation of the workroom should be by means of fans and not simply by open windows. Scouring of china by hand over an open trough into which the ground flint falls should be discontinued. It should be done in semi-closed boxes with a strong down draught on the offside of the workers, or by revolving brushes driven by machinery in semi-closed spaces similarly aspirated. Overalls and coverings for the head should be worn by the workers; and since the form of pulmonary disease that affects potters develops slowly and is capable of being at least retarded, if not arrested, in the early stages, in the interests of the workpeople themselves their chest should be examined by a doctor once every three or six months, so that those who show signs of commencing lung disease might be pronounced disqualified for further employment at towing and scouring.

THOMAS OLIVER.

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XXIII. BASIC SLAG

In the manufacture of steel by the Thomas Gilchrist or basic process, there is a large percentage of waste product, which is known by the name of basic slag. This, notwithstanding its high percentage of phosphorus, remained for some years of little or no value, until it was found that its fertilising properties could be obtained by reducing it to an exceedingly fine powder. Since that was done, it has been in great demand as a manure. It is the manufacture of this manure which is said to produce deleterious effects upon the workmen engaged, and which has brought it within the meaning and regulations of a dangerous trade.

The composition of basic slag is:--

Lime 41.58 per cent. Magnesia 6.14 „ Alumina 2.57 „ Peroxide of iron 8.54 „ Protoxide of iron 13.62 „ Protoxide of manganese 3.79 „ Protoxide of vanadium 1.29 „ Silica 7.38 „ Sulphur 0.23 „ Calcium 0.31 „ Sulphuric anhydride 0.12 „ Phosphoric acid 14.36 „

Before crushing, the slag is in large pieces, and it has to be ground into an almost impalpable powder, so that 80 to 85 per cent. of it will pass through a mesh of 10,000 to the square inch. There is still a more impalpable dust given off which, notwithstanding the utmost care, escapes from the machinery during the process of grinding.

The grinding is performed in several ways, sometimes by means of edge runners, sometimes by flint pebbles, and sometimes by means of heavy balls called the Krupp ball system. The following is a description of the process as carried on at the North Eastern Steel Works, Middlesborough.

The main building is of three storeys, the ground floor of which is used for the various pulleys and driving gear for the mill.

On the first floor are six roller mills, and on the top floor are ten Askam separators, three screens, and a main conveyor, into which each separator discharges the dust.

Outside the main building, but connected with it, on the ground floor, is a shed in which are placed four edge runner mills.

The slag is put into the first edge runner, and crushed until it is fine enough to pass through grids at the bottom of the mill, and it falls through these on to an elevator, which takes it up to the screen on the top floor. That which is not fine enough to pass through this screen falls down into the second edge runner, where it is ground in a similar manner and again elevated to the top floor.

After the slag has passed through the screen, it is taken into the first two separators, where the fine dust is taken out and falls into the main conveyor, and is carried by means of this direct to the warehouse.

The tailings from the separator fall into the roller mills on the first floor, where they are crushed up, after which they fall into the second edge runner mill, where they are ground and treated in exactly the same way as in the first edge runner mill. This process being repeated altogether four times, the slag is then found to be pulverised.

The dust made in the separators is conveyed direct to the warehouse, as above described; but that made by the roller mills on the first floor is drawn by means of a fan into a long tube, running the whole length of the building, and from this it passes into a long dust-tight chamber, called the stive room. The floor of this room is cleaned by scrapers, which take the dust into the main conveyor above referred to. The dust is finally received into a hopper, and from this it falls automatically into bags, in quantities of about a hundredweight.

In the early years of its manufacture, the process was conducted in such a way that it was undoubtedly a very dusty occupation, and the men working at it then suffered constantly from what they called the “slag cough.”

Some two or three years after its manufacture was begun, there was an outbreak of epidemic pneumonia in Middlesborough, and it was thought by many to be in some way caused by the new industry. As the disease (in 1888) assumed very serious proportions, it was thought expedient by the sanitary authority to invite the co-operation of the Local Government Board. Dr Ballard came down, and after a most careful inquiry, he reported that “the slag dust to which the epidemic had been attributed was not the cause of the pneumonia, but that when from any cause pneumonia becomes epidemic, persons largely exposed to the inhalation of this dust may and do suffer more than persons not so exposed, and that the disease with them is of high fatality.”

In 1893 the attention of the Secretary of State was again called to the injurious nature of the trade, and Mr Gould, Her Majesty’s Superintending Inspector of Factories, conducted the inquiry, and made a report in December of that year, in which he says:--“Being in its nature extremely fine, it has a tendency, when inhaled, to settle in the farthest ramifications of the air-passages, and to induce in the mucous membrane of these a chronic state of irritation, thus rendering the larynx and bronchial tubes unduly susceptible of further mischief should the subject take cold; and in general creating a distinct predisposition to bronchitis and pneumonia. Moreover, it is found that when pneumonia does supervene, a fatal result not unfrequently follows, with unusual rapidity. But even in a case of complete recovery from an acute attack, the patient will be constantly liable to a recurrence of the same malady, as his breathing apparatus is continually undergoing deterioration, so long as he is subject to the influence of the dust.”

The summaries of these two inquiries may be taken as representing all that could be said about the effects of slag dust at that time; and it remains for me to state whether more recent observations have tended to confirm these conclusions.

In investigating the subject, I have examined a number of men engaged in daily occupation at the mill, and I subjoin a short report of some of them.

S. R., 54, been in the mill twelve years; well nourished; no complaints except occasional cough after starting in the morning; breath sounds not very distinct at the base of the lungs, and expansion of chest rather deficient.

J. R., 32, worked in the mill thirteen years; chest expansion rather deficient; general health good; occasional cough.

E. F., 31, worked eleven years; good appetite and good health; had pneumonia fifteen years ago; does not suffer from colds, but coughs sometimes in the mornings.

W. J., 44, has worked nine years; always has cough, which is worst about an hour after leaving work; expansion of chest diminished.

J. T., 52, worked thirteen years; health equal to the average. Three years ago had pneumonia; ten weeks off; colds not common; respiratory murmur diminished over the bases of lungs; expansion lessened.

N. R., 44, worked eight years; health good, never ill; colds often.

In measuring the chest, it was found that there was only a difference of about one and a half inches between that of inspiration and expiration, showing considerable diminution in chest capacity.

With regard to the causation of chest affections there can be little doubt that it produces increased action of the bronchial mucous membrane, and consequent cough. But unless this is accompanied by such influences as wet, cold, exposure, or drink, there is no reason to think that it is the cause of acute bronchitis. Indeed, notwithstanding excessive carelessness in their habits, I should say that the tendency in the great majority of cases is towards a chronic affection of the bronchial tubes, followed after some years by emphysema.

The men nearly all suffer more or less from cough and some mucous expectoration, which makes them frequently seek relief from cough medicines. In the last few years, however, great improvements have taken place in the grinding mills, and the men now tell me that their discomforts are greatly reduced.

In the cases examined, there was accelerated breathing in three, and diminished power of expansion more or less in all of them.

It will be seen from the chemical analysis of the slag that there is nothing in it of the nature of a poison such as to produce immediate injurious consequences, beyond such effects as may be traced to its mechanical action upon the bronchial tubes and air cells. The phosphoric acid is in combination with the lime as a tetraphosphate, which is not corrosive, nor generally harmful. There is, however, a good deal of irritation produced in those unaccustomed to it, for on the last occasion when I visited the works, I felt some tightness in the chest, with cough and roughness of the voice, which lasted three or four hours.

Inquiries have failed to elicit that any undue proportion of slag-workers have been attacked by pneumonia. As the medical profession in Middlesborough had come to suspect pneumonia in slag-workers as infectious, with a view to helping in its investigation an arrangement was come to with the Health Department of the Town Council to have the cases of pneumonia notified. Of these, 36 were labourers, and the other 67 embraced nearly the whole catalogue of special workers and trades, such as crane men, gantry men, carters, trimmers, blacksmiths, joiners, fitters, and moulders, besides printers, barmen, publicans, butchers, teachers, and insurance agents.

During the latter half of 1900, Dr Dingle, the Medical Officer of Health, received 103 notifications of pneumonia in adult males, which he inquired into. After a very careful inquiry, Dr Dingle failed to fix any special degree of susceptibility upon any particular occupation. Slag dust does not play any prominent part in causing pneumonia.

In the treatment of the immediate effects of the inhalation of slag dust, the remedies for ordinary catarrhal conditions of the bronchial tubes answer as well as anything; and as its remote effects are in no way different from those produced by other dusty occupations, remedies which prove useful in those, such as potassium iodide, carbonate of ammonia, digitalis, and strychnine, have, in my hands, proved most efficacious.

But our efforts must be directed more to the prevention of the initial ailments, and to the amelioration of their causes than to their treatment by medicines, for it must not be forgotten that the tendency is always towards the production of structural changes in the tissues of the bronchi and lungs.

There is a standing order in all of the works that the men should wear respirators, and these are provided by their employers. But hitherto no form of respirator has been suggested which answers the necessary requirements of being porous and comfortable, and at the same time impervious to dust. The face bag, which was one of the results of Mr Gould’s inquiry, ought to be of great service; but it becomes saturated with the moisture of the expired air, the result being that during inspiration it is drawn up against the mouth and nose, and a sufficient quantity of air not being available, the workmen slip it down underneath the chin, where, of course, it is useless. No contrivance will ever answer the purpose which does not admit of easy access of air into the lungs, and of complete expiration without effort. For this purpose a light, soft wire mask might be made to fit the face, which should stand out from the mouth and nose. It should contain a shutter, by which several layers of open webbing could be enclosed, through which the breath could be easily drawn; and there should be an opening fitted with a valve, which should open easily for outward, but shut for inward breathing.

The finished material is placed in packing bags, in the fitting of which the openings are tightly fixed round the hopper, and by means of a lever the charge is suddenly dropped into the bag, when a cloud of dust immediately rises. There is consequently more dust in this department than there ought to be, and, moreover, it is the finest dust of all, for it comes through bags of very closely-woven texture. If the packing material were dipped in size, or rendered impervious in some other way, this source of danger would be largely reduced.

There is another improvement which might be suggested, and that is, that the men should be provided with a room, outside the mill altogether, in which to take their meals. As it is at present, the grinding goes on without stoppage for meals, which renders it necessary for the men to be on hand the whole time; consequently there is no opportunity for open-air breathing time. By a little arrangement the men could probably go in batches, and have their dinner in comfort, and for a time be free from the atmosphere of the mill.

JOHN HEDLEY.

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XXIV. GANISTER CRUSHING

Workers engaged in crushing basic slag, in the breaking of certain rocks, in the manufacture of millstones, in stone-mason’s work and kindred occupations, are peculiarly liable to chronic inflammation of the air-tubes, caused by the inhalation of dust of an irritant kind. This, it is believed, leads to lung fibrosis. Where the operatives form part of a large community in which individuals are employed in many and varied trades, it is conceivable that fibrosis of the lung may be mistaken for tubercular pulmonary consumption, and it may not be realised that the cause is due to the occupation of the sufferer. The late Dr Arlidge, in a public lecture on “The Sanitation of Industries and Occupations,” referring to china clay as a silicious material, states that the dust is most destructive to lung function and lung integrity, as it sets up chronic inflammation of the air-tubes and of the lung tissues, itself accompanied by bronchitis and asthma. The disease thus established terminates in fibrosis of the lung, “a lesion which symptomatically closely resembles pulmonary consumption.”

The risks referred to have in late years more than ever engaged public attention. Already great strides have been made in the provision of remedies. To medical men practising in districts where these dusty trades form the principal occupation, we may look for information of a definite and exact nature as to the health of the workers. A highly interesting article, entitled “Ganister Disease,” was published in the Journal of the Sanitary Institute for April 1900. The writer, Dr C. L. Birmingham, lived for several years in the valley of the Don, the principal centre of this mining industry.

To the general reader it may be well to explain that ganister or calliard is a hard, close-grained, silicious stone which often forms the stratum that underlies the coal seam. A footnote in Dr Percy’s Fuel says--“Dinas rock is believed to be a millstone grit of the carboniferous system, and the geological equivalent of the bed termed ‘Ganister’ at Sheffield.” It is found in Yorkshire, Durham, North and South Wales, and elsewhere. When crushed and ground into dust it is used as a fire-resistant, chiefly for lining Bessemer and other steel-converters, for the manufacture of bricks likely to be subjected to great and continuous heat, and it is sometimes mixed with, or substituted for, Stannington or other clays, which, together with ground cinders and old ground pot, are used for the manufacture of crucibles in which certain kinds of steel are made.

The persons liable to suffer are the ganister miners and those who manipulate the material in mills known as “breaker-mills.” During the mining process much dust is generated in the various stages of blasting, and little doubt exists that it is to this that we must look for a solution of the very high mortality returns. By many it is held that the products of combustion from the blasting charges are liable, when inhaled, to cause (or to predispose the worker to) chest affections. The ganister, in large lumps, is brought from the mines to the mills in small trucks running on metals. Where necessary, these lumps are broken by hand with heavy sledge-hammers, the process being known as “sledging.” Whilst this is being done a certain amount of dust arises. The material is next thrown into breaker-mills of various patterns, for crushing. The mills are in the open air, or in open sheds. As the lumps are thrown into the mouth of the mill where the crushing takes place, clouds of dry dust rise in the face of the workers, and to this operation is attributable much of the illness. Happily, a remedy generally accepted has been found and is being adopted. It is simply a jet of steam playing into the mouth of the mill, damping the material and preventing the dust from rising. In some works, small fine jets of water, such as would run from an ordinary water can, are preferred. Time has not yet allowed practical men to say with certainty that this is an absolute remedy, but they are very hopeful.

The crushed ganister, in pieces about the size of “metal” used for road-making, is carried from the breaker-mills by shoots to edge-runner mills, to be pulverised into a fine dust. During the whole of this process it is thoroughly saturated with water, rendering the escape of dust a practical impossibility. In this state it is ready to be converted into bricks, or to be taken away in railway trucks, carts, or other conveyances, for use elsewhere. It is sometimes found that the ganister mortar is too moist, in which case it is “tempered,” that is, dry ganister-dust, to the necessary amount, is mixed with it. In this process some dust may here arise, but it is hardly in sufficient quantity to affect the health of the workers.

The bricks are made in hand presses. It is not a dusty process until just before closing the press, when many operatives take a handful of ganister dust and throw it over the surface of the brick, to secure a clear and clean impress, showing the name of the maker, etc. This is a dangerous and unnecessary step; damp sawdust is equally efficacious and is now generally used. The floors of ganister brick-drying sheds, as in other brick works where the same method of drying is adopted, are more or less dusty. Under these floors there are pipes heated by steam or hot air, for the purpose of drying the bricks. Each time a dry brick is lifted, dry dust is liberated, but seeing that there is little or no traffic on these floors (except in passages, which can easily be kept clean), the dust rests on the floor, and does not permeate the atmosphere. Mechanical fans have been suggested, but practical men would find it extremely difficult, if not impossible, to find any fan that would carry this dust, and such men certainly would be sceptical as to the wisdom of creating draughts where the desire is to keep the dust on the floor, and not to cause it to fly about. It will be realised that although fans may be, and are, used with the greatest advantage in certain dusty occupations, it does not follow that they will answer in all.

It has been stated, and probably with some degree of accuracy, that the “setter’s” work involves exceptional risk. The process consists in placing the bricks in the kilns for baking, after they have been dried in the sheds. A man standing in an elevated position catches the bricks, which are thrown to him by the man at the mouth of the kiln. As they are thrown, dust is liberated, and seeing that this work is done in a confined space, it is quite conceivable that injurious results to health may follow.

In some works ganister is ground dry in what are known as “sieve mills.” These are ordinary edge-runner mills, with a sieve at the bottom of the pan. The fine ganister passes through the sieve, and is taken by elevators to the sifting machine, where what is fine enough is carried away to the receptacle for holding it, the coarser material being carried by shoots to be again ground in the mill. In many works the ganister, although nominally dry, is damped sufficiently to prevent any escape of dust, and it has been stated by experienced manufacturers that the damping in no way damages the material, nor does it hinder the work. This dry ganister crushing is in most cases a subsidiary process, the quantities required being small, it only being used for the purpose of making a cement, or mortar, for joining silica bricks or other fire resistants.

Ganister workers are peculiarly liable to those ailments incidental to occupations exposing the operatives to extremes of heat and cold, to damp, and to draughts, but the writer believes that he has, in general terms, defined the peculiar and exceptional risks incurred in this occupation. Having done so, it seems difficult to account for the alarming mortality returns published in Dr Birmingham’s article. A possible solution may be found in the fact that where ganister works are situated there are also large numbers of fireclay works in which are made fire-resisting bricks, tuyeres, pipes, gas-retorts, etc. To the uninitiated it might appear that ganister and fire-brick workers were engaged in one and the same occupation, nor would this be unreasonable when the constitution of the two substances is considered. Ganister is stated to contain 95 per cent. of silica, whereas, according to Chambers’s Encyclopedia, from which the following extract is taken, it will be seen that fireclay contains from 54.2 to 65.1 per cent. of silica.

“Ordinary fireclay is chiefly found in beds not usually much exceeding two feet in thickness, in the coal measures, interstratified with seams of coal and other rocks. In the British Islands it is most largely worked about Glasgow, Newcastle-on-Tyne, and Stourbridge in Worcestershire, at which last place it is said to have been discovered about 1555 by some wandering glass-makers from Lorraine. But it occurs, more or less, in most places where true coal is found. It is mined in Germany, Belgium, France, the United States, and other countries. Stourbridge fireclay, owing to its excellent quality, is largely exported to foreign countries, as well as bricks and other objects made of it. Refractory clays are found, although more rarely, in other formations besides the coal measures. For example, some of Tertiary age found in Dorsetshire and Devonshire are made into firebricks. The following table shows the principal constituents of fireclay:--

+----------------+--------+--------+--------+--------+--------+ | | No. 1. | No. 2. | No. 3. | No. 4. | No. 5. | +----------------+--------+--------+--------+--------+--------+ | Silica | 65.10 | 51.10 | 59.49 | 53.52 | 54.20 | | Alumina | 22.22 | 31.35 | 28.95 | 33.68 | 33.80 | | Potash | 0.18 | ... | ... | Trace | Trace | | Lime | 0.14 | 1.46 | Trace | 0.76 | Trace | | Magnesia | 0.18 | 1.54 | ... | 0.14 | 0.02 | | Oxide of iron | 1.92 | 4.63 | 1.05 | 0.52 | 0.01 | | Water | 9.28} | 10.47 | {11.05 | 11.34 | 10.86 | | Organic matter | 0.58} | | { ... | ... | 0.15 | +----------------+--------+--------+--------+--------+--------+

No. 1, Stourbridge; No. 2, Newcastle-on-Tyne; No. 3, Gartsherrie, Scotland; No. 4, Poole, Dorsetshire; No. 5, Morgantown, West Virginia, United States.”

Ganister is pulverised in the wet state. Fireclay is not moistened, but ground into a fine dry powder, certainly suggesting greater risk to the workers.

Into other industries, such as the manufacture of steel-melters’ composition, the crushing of ganister largely enters. This composition is used for the manufacture of heavy castings, and contains large proportions of old ganister and fireclay crucibles, bricks, mortar, etc., which are ground in open edge-runner mills in the dry state, fed, and often sifted by hand. The work is generally done in the open air or in open sheds, where the dust is blown about, and where it is a practical impossibility for the worker to avoid inhalation of this irritant. The use of closed mills, closed cylindrical worm-screw conveyers, and mechanical sieves, would largely avoid unnecessary risk, and these labour-saving appliances (the writer believes) would soon more than repay any original cost.

The sickness and mortality amongst ganister workers engaged the attention of the poor-law authorities in the district of Deepcar, near Sheffield. Statistics were prepared for them, and a very carefully considered report dealing fully with the subject was submitted by Dr Robertshaw of Stockbridge, Medical Officer of Health for the division.

The attention of Dr Legge, H.M. Medical Inspector of Factories, was called to the subject recently, and he obtained from Dr Robertshaw the lung of a ganister miner, who had presumably died from pneumoconiosis. The following is an extract from the valuable report by Dr F. W. Andrews, Pathologist to St Bartholomew’s Hospital, of the anatomical changes in this lung induced by the inhalation of ganister dust, published in Dr Legge’s Report to the Chief Inspector of Factories for the year 1900.

Report on Portions of Lung from a Ganister Miner.

The upper lobe is densely indurated, black and fibrotic. The pleura is thickened, especially at the apex. The lower lobe shows less advanced changes; numerous blackish nodules, about the size of a hemp-seed, are scattered throughout its substance with tolerable uniformity. Under a lens many of these indurated patches are seen to contain a minute cavity, as if they had been formed around minute bronchi or blood-vessels. The intervening lung tissue is greyish, scarcely at all pigmented, and not indurated; it has the appearance of slight uniform emphysema. The large and medium-sized bronchi stand out prominently. To the naked eye the lung nowhere shows any evidence of tubercle.

Microscopic Examination.--Seven different blocks of lung tissue were selected illustrating as far as possible the different degrees of fibrotic change present, from an area almost normal up to the densest induration. These were sectioned. The method of staining found most suitable was that known as Van Giesson’s--viz., staining in hæmalum, followed by a counterstain of acid fuchsin with picric acid. In this way the distribution of the fibrous tissue was demonstrated with great minuteness. Nuclear staining was not very well marked, because the tissue had been lying so long in spirit.

All sections show an abundance of foreign mineral particles of a black or brownish colour. The majority of these are minute, irregular, sometimes angular in form. Seen singly they are semi-transparent and brownish, but they are commonly collected into blackish heaps, included in cells, and then appear opaque. Careful focussing, however, reveals the presence of the angular semi-transparent particles in these accumulations. The pigment masses have not the soft and rounded outline of the carbon masses seen in the lungs of town dwellers; nevertheless very finely divided jet black particles are present, which are probably carbon, but they are less abundant than the brownish semi-transparent masses. The pigment masses occur chiefly in connection with the fibrotic areas.

A few simple chemical tests were applied to microscopic sections, and their effect watched under the microscope. Caustic potash (10%) produced no change whatever in the pigment. Glacial acetic acid likewise caused no change. Fuming nitric acid caused liberation of gas bubbles under the coverglass, but the colour and amount of the pigment were in no way altered. From this it may be concluded that the colour does not depend upon altered blood or any organic product, but that the pigment is purely mineral in character--carbonaceous or siliceous. The liberation of gas by nitric acid indicates the presence of traces of carbonates.

The characters of the fibrotic change and its localisation and development could be traced from its earliest commencement. Sections of the least affected portions of the lung present the following appearances. The pleura is scarcely thickened over much of the lower lobe. There is a slight degree of diffuse emphysema; apart from the indurated patches there is a very slight increase in the amount of fibrous tissue present in the alveolar walls generally, but in some places this is barely perceptible. Careful search in the alveolar walls reveals the presence of scanty mineral particles scattered in the tissue. In places these form larger clumps. Some few detached epithelial cells, laden with pigment, are seen here and there in the alveoli; but on the whole, except around the fibroid nodules, the pulmonary epithelium shows no sign of proliferation or catarrh. There is no evidence of general broncho-pneumonia and none of vascular congestion.

The development of the fibroid nodules appears to take place in the first instance around the small arteries, veins, and bronchi. Where a vessel chances to be cut longitudinally, the perivascular thickening is seen to be irregular and patchy, whence arises the appearance of discrete fibroid nodules. When cut transversely, nearly all the blood-vessels display some degree of perivascular fibrosis. This is true also of the bronchi; but these have undergone so much loss of mucous membrane that it is not always easy to say which are bronchi and which blood-vessels. It is not possible to be sure that all the young fibroid nodules have this perivascular or peri-bronchial origin. Some appear to be independent of vessels or bronchi, but it is possible that they are tangential sections of such thickenings. It seems clear, however, that most own such an origin. In any case the relation between the accumulation of mineral particles and the production of new fibrous tissue is obvious and beyond dispute.

Older and denser nodules, such as are visible to the naked eye, as the hemp-seed structures above described, illustrate the further development of the process. In those the vessel or bronchus around which they have presumably arisen has usually disappeared, and they present concentric zones which represent different stages in their formation, and illustrate the manner in which they increase in size. The outermost zone shows the earliest stage: large black pigment-laden cells accumulate; they may be in part leucocytes, in part pulmonary epithelial cells or fixed connective tissue corpuscles. The pulmonary epithelium is here often in a condition of catarrhal proliferation--a localised broncho-pneumonia--each cell full of mineral particles. The next zone consists of a loose connective tissue, the meshes of which contain the large pigment-laden cells previously mentioned. The mineral matter is almost entirely intracellular. The central mass is composed of a dense fibrous tissue in which the cells have almost entirely disappeared, the mineral particles now becoming free and less conspicuous because they are no longer aggregated into dense black clumps. It is easy to realise from the structure of such nodules how they increase in size at the expense of the lung tissue. Beneath the pleura a similar development of new pigmented fibrous tissue similarly occurs. It is to be observed that all this fibrotic change corresponds in its localisation with the distribution of the lymphatic system of the lungs. The lymphatics, originating by stomata between the pulmonary epithelium, fall into two sets--(1) the sub-pleural network, and (2) those which closely accompany the blood-vessels and bronchi, forming a perivascular and peri-bronchial network.

The final stages in the process are shown by sections taken from the upper lobe of the lung, in which the fibrosis is much more dense and complete. Here the individual nodules have so encroached upon the lung tissue that they have more or less completely coalesced. In the most advanced portions, little or no normal lung tissue can be seen, although the focal character of the fibrosis is still perceptible, since islands of dense fibrous tissue are connected by areas in which the pigmental cells are enclosed in a looser connective tissue. The mineral particles are here even more abundant and conspicuous than in the lower lobe of the lung. In one single nodule (in the lower lobe) calcification was seen, but this stage is absent elsewhere.

Although to the naked eye there is no evidence of tubercle in the lung, yet microscopically such evidence exists in at least one of the seven blocks. The process of fibrosis has been traced from its earliest stages, and is most positively non-tubercular in its origin. The evidence of tuberculosis is present, as a recent and accessory phenomenon, only in the most advanced stages of the fibrotic change. It consists in the presence of small miliary tubercles embedded in the fibrous tissue, and showing the characteristic structure of tubercles, with typical giant cells. Even in these no tubercle bacilli can be demonstrated.

The conclusions to be drawn from the preceding observations are as follows:--

The inhaled mineral particles are, in the first place, deposited uniformly in the pulmonary parenchyma. They are at once taken up hence by the lymphatics and carried along by the lymph stream. The lymphatics have a perivascular, peri-bronchial, and sub-pleural distribution, and in these situations the mineral matter specially accumulates, because the amount is greater than can be got rid of by the lymphatics. It is here chiefly found enclosed in cells (phagocytes), and exercises an irritant action leading to the production of new fibrous tissue in these situations. The fibroid areas increase at the expense of the adjacent lung, in part at least by the development of a localised broncho-pneumonia, and in part by thickening and induration of the alveolar walls. When the fibrous tissue is fully formed the cells containing the mineral particles break up and degenerate, and the particles again lie free amongst the fibrous tissue. By the spread and coalescence of the fibroid areas, the lung tissue in the most advanced areas completely disappears. A secondary tubercular infection has now taken place, and miliary tubercles appear in scanty numbers in the fibroid areas.

Chemical Analysis.--Portions of the lung were handed to Mr H. A. Schölberg, M.B., who furnishes the following analyses.

The material supplied was dried at 100°C. on a water bath for three hours. The dry lung tissue thus obtained was used for analysis.

(1) Analysis for total Ash. Grammes of dry lung taken 2.2675 Loss of weight on combustion in muffle furnace 1.1900 Residue of ash 1.0775 ∴ Percentage of ash in dried lung = 47.519

(2) Estimation of Silica. Grammes of dried lung taken 0.1505 Silica in the same 0.0100 ∴ Percentage of silica in dried lung = 6.644

HAMILTON P. SMITH.

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XXV. MILLSTONE BUILDING: FRENCH BUHRSTONE

In the Final Report of the Dangerous Trades Committee of the Home Office,[79] the subject of the building or making of millstones by a hard, flint-like stone known in the trade as French buhrstone, and which is imported into this country from Epernon in the Valley of the Seine, and from Fierté-sous-Jouarre, is fully discussed and the dangers exemplified. Buhrstone is one of the hardest stones in nature. It is a variety of quartz, and is so hard and destructive to the steel tools used by the workmen that in ten minutes a workman will knock off the points of as many chisels. The stone has to be shaped into wedges of varying size. These wedges are placed together in the form of a circle cemented together, and subsequently surrounded by one or more strong iron hoops. The millstones are used for grinding flour, cement, feeding stuffs, etc. The chiselling of the buhrstone is generally conducted in the open air or in a shed open at the sides, the rough stone resting meanwhile upon a tub filled with sand, or upon some other solid support. Fortunately French millstone building is a small industry, for it is one that is most destructive to human life. Millstone masons are a short-lived body of men. Their work is hard, most of it is done practically in the open, without adequate protection from cold, wind, and rain; the wages earned are good, often as much as fifty or sixty shillings a week, but as a class the workmen are intemperate and careless. No doubt alcoholism and indiscretion play their part in shortening the lives of the men. As the stone is very hard, and the point of the steel tools with which the men chisel is readily knocked off, the workmen are exposed to two dangers: (1) splinters of steel and stone striking the eye; and (2) inhalation of the dust given off with each stroke of the hammer. Considering the compactness and the great weight of the stone, it is astonishing that the dust evolved in chiselling ever reaches the lungs at all. In dealing with the question of dust generated in any trade, it is to be remembered that while the dust that is seen lying about in a factory may seem to be heavy and the particles large, yet there is a finer and more impalpable dust created at the time the particular work is being done, and it is very largely this which is inhaled and inflicts the damage. When a workman is chiselling a piece of buhrstone, two different kinds of particles are given off, mineral particles from the stone, and metallic from the chisels. These mingle together and form the dust that is inhaled. That steel particles are present in the dust rising from the stone was indicated to my colleagues on the Departmental Committee and myself by a workman who, having magnetised the blade of a pocket knife, placed the same in his waistcoat pocket, and “after moving it about a few moments withdrew it, when it was found to be covered along its edge with a fern-like coating consisting entirely of minute particles of steel.” It is to the presence of very small fragments of steel imbedded in the skin of the arms of the men, who frequently chisel with their sleeves rolled up, that is due the bluish-black mottling of the forearms of millstone builders.

The men, as already stated, are short-lived. Several whom I examined in the stoneyards on the banks of the Thames acknowledged the unhealthy character of their employment, and said that they and their comrades knew they might be able to follow their calling for only ten or fifteen years, seldom more, and that probably before the tenth year was reached, symptoms of pulmonary consumption would show themselves, attended by cough and blood-spitting. Hæmoptysis is a very common symptom, and in this respect, as also in the rapid course of the illness, the pulmonary consumption of millstone builders differs from the phthisis of potters in which hæmorrhage from the lung is rather infrequent. Once destructive changes have been started in the lungs of a buhrstone chiseller, the disease progresses quickly to a fatal termination. The Dangerous Trades Committee found that men who began this occupation when very young seldom lived beyond thirty-six to forty years of age.

Prevention.--It is such a dangerous occupation that if the industry were swept out of existence altogether it would be no great loss either to the commercial world or to civilisation at large. The number of men employed in it is small, and as steel rollers have to a large extent replaced French millstones in the grinding of food and other stuffs, milling can be just as successfully accomplished without as with these stones. The trade will probably die a natural death, but so long as the industry continues, the men ought to wear respirators. If this were done much illness would probably disappear. The men complain of the irksomeness of respirators, and of the heat that they cause. The laborious nature of their employment creates a need for free, full, and easy respiration. The dust that is given off in chiselling the stones is very heavy, and is therefore capable of being readily carried downwards and away from the workmen by powerful suction, yet the conditions under which the work is carried on, viz., in open places and unprotected sheds, makes the use of fans difficult, if not impossible. The wearing of goggles or eye-guards should be insisted upon.

THOMAS OLIVER.

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XXVI. STEEL GRINDING

The process of grinding cutlery and other steel implements is conducted by a class of workmen known as “grinders.” Their trade is a highly specialised one, necessitating a long apprentice-ship before proficiency is attained; and in the majority of instances the calling has been handed down through many generations. The trade is quite free from the adulteration of casual labour, and consequently statistical data respecting “grinders” possess a relatively high value. For the most part they earn good wages, and being keen sportsmen, get a fair amount of outdoor recreation. Their hours of work are seldom excessive, and their homes and mode of living are up to the average standard of comfort obtaining in the artisan class of the population.

Grinding is done on circular stones turned either by steam or water power. The stones vary in diameter from an inch up to several feet, and are of different degrees of hardness according to the work required of them. On the stones, articles of cutlery are reduced to their proper shape and thickness, and are given their cutting edge, while many other steel implements are ground to remove the roughness of their surfaces. For the most part “grinders” sit astride the grinding stone on a saddle, leaning forward, more or less according to the size of the stone. The position is not an ideally healthy one, but the assertion that it interferes with the free expansion of the lungs is only to a very slight extent true. The attitude, however, renders the workmen peculiarly vulnerable to accident when a stone breaks.

Grinders are divided into two classes, known respectively as “dry grinders” and “wet grinders.” The former are engaged in grinding steel forks, augers, gimlets, needles, and a few other articles; while the latter grind the blades of knives, scissors, razors, and most other cutting implements.

Certain articles of cutlery are ground partly on a wet and partly on a dry stone. Thus the backs of razors and scissors and the bolsters of table-knives are ground dry, while the rest of the blade is wet ground.

Dry grinders form a comparatively small class of workmen, but owing to the excessive mortality which formerly obtained among them they have long attracted the attention of the trade sanitarian. The attrition of the steel against the dry grinding stone gives rise to enormous quantities of steel and stone dust, which renders the atmosphere of the workshop very irritating to the lungs, and produces a pathological condition known as grinders’ phthisis.

The following account of the pathology and symptomatology of the disease has been very kindly written for this article by Dr Duncan Burgess, Senior Physician to the Sheffield Royal Hospital:--

“Grinders’ Phthisis, Grinders’ Asthma, Grinders’ Rot.--This disease is due to the inhalation of dust composed for the most part of gritty particles from the grinding-stone, but also containing fine particles of steel from the implement ground. It has been asserted that steel particles are not found in the grinders’ lung, but a very beautiful microscopical section of an affected lung, appropriately stained, in the possession of Dr Arthur Hall, shows unmistakably traces of iron. Steel dust, however, constitutes only a minute fraction of the foreign pigment in the diseased lung, and its effects compared with those of stone dust may be neglected.

“The frightful mortality among dry grinders before the introduction of fans made the lung diseases of this class of workmen so notorious that the name ‘grinders’ phthisis’ still signifies outside Sheffield the very severe indurated broncho-pneumonia, which past generations of fork grinders were subject to. This extreme form of grinders’ phthisis is now practically extinct, but a modified form of the disease is still very prevalent among Sheffield grinders and cutlers. The whole respiratory tract is exposed to the action of the dust, but its effects on the larger passages are comparatively unimportant. The disease usually manifests itself in the first instance in the form of chronic bronchitis with emphysema. Immunity from symptoms may continue for decades, then in the winter or during foggy weather cough with some expectoration in the morning may be noticed. The cough gradually gets worse, and it may last more or less throughout the winter. Shortness of breath is now complained of, and the grinder may have to leave off work for weeks together from time to time. Finally his cough persists through the summer, and his shortness of breath on exertion forces him to leave off work altogether, it may be after the age of sixty, or even twenty years earlier. If he be examined now his skin and lips will be dusky, and his chest fixed as at the end of inspiration. The breathing is mainly diaphragmatic, and though the auxiliary muscles of respiration stand out in strong contraction, there is very little expansion of the chest. In addition to the ordinary physical signs of bronchitis there may be areas in which the breath sounds are very feeble or absent, and areas in which they are comparatively loud. The grinder is especially liable to have tuberculosis grafted on to his bronchial lesion, and this may occur quite early, or be deferred until late. Wasting, night sweats, and hæmoptysis mark the onset of the rapid change for the worse which follows tubercular infection. The dyspnœa is naturally greater than in ordinary phthisis, and the emphysematous condition of the lung may mask for a time tubercular infiltration. The sputum is at first very scanty, and consists of mucus with dark spots and patches. Later it is more abundant and becomes muco-purulent, with black spots and patches, and occasionally gritty particles. In the terminal stage tubercular bacilli are present, together with other pathogenic organisms. Grinders suffer inordinately from pleurisy and pneumonia.

“The pathological feature of dry grinders’ phthisis is the presence in the cut section of the lung of groups of dark, hard nodules about ⅓ of an inch in diameter. Under the microscope these nodules are found to consist of dense fibrous tissue arranged more or less in layers. Black amorphous masses may be conspicuous in or near the centre of the nodule. The lung tissue in immediate contact with the nodules is converted into less dense but more deeply pigmented fibrous tissue. This merges into air-cells with thickened and pigmented walls. The apices of the lungs are more frequently the seat of nodules than the bases. In an extreme degree of grinders’ phthisis the entire upper lobe may be replaced by a solid, hard, black mass, which on section presents a mottled appearance from the innumerable nodules, thickened bronchi, and pigmented airless lung tissue. The pleura is irregularly thickened, in places forming a milky or thick yellow layer, which may be adherent to the chest wall. A tubercular cavity of considerable extent may be found at the apex or elsewhere.”

At one time dry grinding was perhaps the most unhealthy trade in the country. The late Dr J. C. Hall of Sheffield, in a paper read before the Social Science Congress in 1865, stated that “excluding boys, the average age of dry grinders was only twenty-nine years;” and there can be little doubt that comparatively few workmen were to be found following their employment after the age of forty years. Of late the introduction of fans for carrying away the dust has greatly improved the conditions under which dry grinders work, and, as I shall presently show, this has been followed by a corresponding improvement in health and length of years, but the trade is still an unhealthy one.

Wet grinding is much the more important branch of the grinding trade, and in Sheffield alone it gives employment to several thousand workmen. In revolving, the grinding-stone passes through a thin layer of water placed in a trough beneath the stone, and is always wet, so that comparatively little dust is produced; but as certain other dust-producing processes are usually conducted in the wet grinding workrooms, the atmosphere is not quite free from dust. The processes referred to are:--

(1) Glazing.--Most articles of cutlery after having been ground are “glazed.” This is done on a wooden wheel covered with leather which has received a coating of emery and glue. The rim of the wheel is from time to time rubbed with a cake composed of emery, suet, and beeswax. The “glazer” is used for the purpose of removing marks on the blade left by the grinding-stone. Owing to the greasy nature of its surface there is not much dust formed.

(2) Polishing is employed to give a highly-finished appearance to certain blades. The “polisher” is also made of wood, covered with leather, but instead of emery a fine powder containing oxide of iron, and known as “crocus,” is used. The process gives rise to a considerable amount of dust.

(3) Lapping.--The blades of pen-knives and many razors are subject to a process called “lapping,” which is done on a lead-rimmed wheel called a “lap.” The process is chiefly interesting as being a possible source of lead poisoning, but after careful inquiry I have failed to find any one showing evidence of plumbism from this source.

(4) Racing the Stone.--The grinding-stones are received from the quarries in a rough condition, and the “grinder,” after mounting the stone on its axle, reduces its circumference to the proper shape and degree of smoothness by applying a steel bar to it while it is revolving slowly. This process, which is known as “racing the stone,” gives rise to enormous volumes of dry dust, so that the air in the immediate neighbourhood of the stone is almost unbreatheable. All stones, whether for wet or dry grinding, require to be “raced” in the first instance.

But while wet grinders cannot be said to suffer much from the irritation of dust, they show an appalling mortality from phthisis and other diseases of the lungs, and there is no room for doubt that the damp, stagnant atmosphere in which they work is the principal cause of these diseases. The grinding-stones are constantly throwing off water, which soddens the floor and saturates the air of the grinding-room until, owing to the absence of efficient ventilation, it becomes very like that of a damp cave.

Another danger to which grinders are exposed is the breaking of the grinding-stone when in motion. These accidents are unfortunately common, and often cause frightful injuries and death. They are due to a variety of causes, such as departure from the circular shape owing to one side of the stone wearing faster than the other; flaws in the stone; allowing the lower part of the stone to remain immersed in the water trough when not in use; fixing the stone on its axle by means of wedges instead of using plates and screws for this purpose; and permitting the stone to revolve too rapidly.

In the hafting of certain classes of knives an emery wheel is used for shaping the knife handles, and it produces dense volumes of dust composed of steel particles from the rivets and tangs, also of emery from the wheel, and of bone or other material of which the knife handles are made. This emery wheel is known as a “cutler’s glazer,” and is a comparatively recent invention, having come into general use only during the last twenty-five years, previous to which all handles were shaped with a file. It is most injurious when used for shaping the handles of knives that have scale tangs.

The cutlery manager of one of the largest firms in Sheffield assures me that cutlers as a class have become much more unhealthy since the introduction of the glazer. This opinion is endorsed by other competent observers, and there is no difficulty in accepting the accuracy of it if we reflect that the modern scale tang cutler who uses a glazer is virtually a “dry grinder.”

Grinding is carried on either in separate buildings, which are known as “grinding wheels,” or on premises where other branches of the cutlery trade are conducted. In either case the grinding of heavy articles is done on the ground floor. The rooms, or “hulls,” as they are called, are sometimes sunk below the level of the ground, and are as a rule bounded on three sides by blank walls without adequate provision for cross ventilation. The windows and doors are in the fourth wall, and the former are usually devoid of glass because the mud from the grinding-stones would speedily obstruct the light if glass were used. The hulls are provided with fires for drying the blades, but the fireplaces are situate in front or in one of the lateral walls, and consequently their utility as ventilating agents is not great. Each hull contains one, two, or more troughs which run from front to back, and in them are placed the grinding, glazing, and polishing wheels in the order mentioned. The floors are wet and dirty, and the atmosphere damp and stagnant, particularly at the back, where it is further defiled by the dust given off from the polishing wheels. The cubical space per worker would as a rule be ample if the ventilation was good.

Dry grinding and the lighter branches of wet grinding are carried on in rooms in the upper stories. Better ventilation exists here, but on the other hand the rooms are often overcrowded, and when dry grinding is done there is of course much dust. In the majority of dry grinding rooms fans for the removal of dust are to be found, but occasionally these are absent. One fan is as a rule sufficient for several workmen. Attached to it is a number of tubes, each of which ends in an expansion or hood in front of the grinding-stone. The tubes are put down by the owner of the factory, who likewise occasionally supplies the fans; but as a rule the fans and hoods belong to the workmen, who are known as “piece workers.” When properly constructed and looked after, the fans act admirably for removing dust, and also aid in ventilating the workshops; but as several workmen commonly occupy one room and share responsibility for its sanitary condition, there is the usual failure to carry out efficiently that which is the duty of one in particular. For this reason the tubes are apt to become choked from not being periodically cleaned out, or a trivial defect which a few minutes would suffice to remedy, is allowed to render the fan inoperative for days together. Again, a careless grinder by neglecting to use a hood will seriously discount the efforts of his more careful shopmates to keep down dust. Hence it happens that in many workshops where dry grinding is done the dust accumulates in large quantities on the floor, to rise in dense clouds each time it is disturbed.

In the manufacture of scale tang cutlery, in which glazers are extensively used, the atmosphere under the most favourable circumstances is charged with fine dust. This is especially noticeable where bone is employed for hafting. Moreover, manufacturers complain bitterly that the workmen will sometimes block up ventilators and dispense with the use of fans unless strict vigilance is maintained. It is almost incredible that any one should pursue so suicidal a policy, yet personal observation compels me to admit that these allegations are not altogether groundless.

Another grave defect is the indiscriminate mixing of various classes of workers. Thus in a shop where a dozen men work, only two or three may be engaged in dust-producing processes, yet all are obliged to inhale the dust-laden atmosphere.

The buildings in which grinding and hafting are done vary widely in their sanitary aspects. Many of these places are as perfect as it is possible to make them, having regard to the nature of the work carried on therein; but not a few are just the reverse. Dilapidated buildings, constructed in the first instance without regard to the requirements of health, are sadly too common. In these overcrowding, defective ventilation, and a dust-laden atmosphere are the rule rather than the exception. Externally the condition of affairs is often no better, the factories being shut in by other buildings which exclude sunlight from the lower rooms, and interfere with the circulation of the air.

Trade mortality tables have been carefully compiled by successive Medical Officers of Health for the city of Sheffield, showing the number of deaths, the principal diseases which cause death, and the age at which death took place in a number of trades. The figures have reference to males over the age of fifteen years, and when contrasted with the corresponding figures of the Registrar-General for the entire male population of the country they indicate fairly accurately the relative unhealthiness or otherwise of the workmen concerned. An examination of the returns for grinders shows an appalling death-rate from phthisis and other diseases of the respiratory organs. Thus in every thousand deaths among grinders phthisis causes 345, and other respiratory diseases 295, or collectively these diseases account for 64 per cent. of the entire mortality, whereas among the entire adult male population of the country phthisis accounts for 144, and other respiratory diseases for 182, in every thousand deaths, or collectively to 32.6 per cent. If we examine the ages at which deaths occur, a similar unsatisfactory contrast obtains. Thus 458 grinders in every thousand die between the ages of thirty-five and fifty-five years, as compared with 261 in every thousand obtaining among the entire male population of the country; while only 140 grinders in every thousand have attained the age of fifty-five years and upwards at death, as compared with 391 in every thousand for the entire adult male community.

The dusty nature of a dry grinder’s occupation prepares us to accept these figures as applied to him; but it must not be lost sight of that dry grinders form a very small minority of those engaged in the grinding industry. Moreover, my investigations lead me to believe that dry grinders, although they still show an enormous mortality from phthisis and other respiratory diseases, live to a much greater age than formerly. Thus I found the average age of twenty-two unselected fork grinders to be forty-three years, which is a marked improvement compared with the late Dr Hall’s estimate of twenty-nine years. Again, during the four years 1889–92 the average age at which fork grinders in Sheffield died was forty-five and a half years.

Owing to the conditions already set forth as existing in many grinding rooms, wet grinders are frequently compelled to inhale dust-laden air, and this no doubt is a factor in producing the high mortality which prevails among them. But important as this evil is, it is altogether overshadowed by the baneful influence of the damp, stagnant atmosphere of the wet grinding “hulls,” an atmosphere which is peculiarly favourable for the propagation of diseases of the lungs.

The legislature of this country has done much to improve the conditions under which workmen pursue their various callings, but local peculiarities and unforeseen contingencies sometimes frustrate the beneficent intentions of our legislators, and this is markedly the case in respect of the grinding industry. With few exceptions grinders are “piece workers,” and pay rent for their “stalls” and the motive power which drives their stones. The grinding wheels and cutlery works are frequently owned by individuals or companies who are not themselves manufacturers, but are merely the landlords of the premises, letting off rooms or portions of rooms to workmen who, in the eyes of the law, are the occupiers, and therefore responsible for carrying out the requirements of the Factory Acts. It follows that the owners of the premises are able to repudiate responsibility for sanitary control and that the Factory Inspector, when he wishes to insist on fans or other needful appliances being provided, must proceed legally against the workmen. The outcome of all this is that it is difficult or impossible to apportion responsibility for sanitary requirements; the Inspector’s work is enormously increased, and often rendered excessively irksome; while the amount of good he can do is proportionally lessened. There is but one remedy for this state of things. Sooner or later the legislature will have to fix on the individual, or company, who lets off rooms and power to workmen, the responsibility for carrying out the provisions of the Factory Acts. We shall be told that an enactment of this kind would disturb long-established trade usages, and be unfair to the manufacturers; but apart from the fact that it is the only feasible way out of the difficulty, it would merely place cutlery manufacturers on the same footing as that occupied by most other employers of labour in the country. Moreover, some of the best cutlery firms already recognise their moral responsibility in this respect, and provide for the use of their workmen fans and all other contrivances of a health-saving nature.

The sanitary condition of the workshops in which grinders, particularly wet grinders, work admits of much improvement. These rooms should always be above the level of the ground, and so situated in regard to surrounding buildings as to allow of free entrance of fresh air and sunlight. The floors should have a fall to the front, and be composed of concrete or some similar impervious material. Better ventilation is urgently required, especially towards the back of the rooms, and the fireplaces might with advantage be placed at the back. The polishing wheels should be provided with hoods connected with a fan for the removal of dust and the better ventilation of the room.

Grinding-stones should not be mounted until they have been inspected by some competent person with the view to detecting flaws, and it should be obligatory to use plates and bolts instead of wedges for fastening the stones on their axles.

Dry grinding should be done in rooms specially set apart for this purpose, and not, as is sometimes the case, in rooms where other processes are carried on. The “racing” of stones should be conducted at a time when there are few workmen present, and those engaged in the process should wear some form of respirator.

SINCLAIR WHITE.

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XXVII. PHOSPHORUS AND LUCIFER MATCHES

However useful phosphorus has been to man, its manipulation has been a constant source of danger. As there are two forms of phosphorus, so there are two kinds of matches: the safety, which-only ignite on the box, and the ordinary strike-anywhere. Safety matches are made from red or amorphous phosphorus, and the ordinary matches from white or yellow. Oldbury, near Birmingham, is the seat of the manufacture of yellow phosphorus. Although white phosphorus is a dangerous substance, there have been very few cases of ill-health among the men who make it, owing very largely to the fact that in its production from bone, very few people are employed, and the processes of manufacture are such that the workmen are not brought directly into contact with the dangerous substance. Sixty tons of the phosphorus annually manufactured in Oldbury are consumed in lucifer match works in Britain.

The death of a lucifer matchmaker in London five years ago, and the announcement in the daily press of the contemporaneous occurrence of a large number of cases of ill-health in a Metropolitan match works, aroused an amount of feeling, and created such an adverse public opinion in regard to this industry in England, that the Home Secretary, Sir Matthew White Ridley, appointed a Commission, composed of Professor T. E. Thorpe, Dr George Cunningham, and myself, to undertake an inquiry into certain important questions which had arisen with regard to the effect of work in lucifer match factories on the health of the workpeople.

The questions which at the time engaged the attention of the Home Office were:--

(1) The nature and extent of the dangers attending the use of yellow and white phosphorus.

(2) The means whereby these can be lessened.

(3) The practicability of discontinuing the use of yellow and white phosphorus.

Many match works, both at home and abroad, were visited by the members of the Commission, whose views and opinions upon these questions are embodied in a Report[80] that describes the methods of manufacture, and the legislative measures adopted in most of the countries in Europe to abolish or diminish the ill-effects of the industry upon the health of the workpeople.

The principal malady of the lucifer matchmaker is a localised inflammatory affection of the jawbone, followed by suppuration and death of the bone, constituting what is known as phosphorus necrosis--“phossy jaw,” as it is sometimes called in this country, and mal chimique in France. Other diseased conditions are also met with, but these and the subject of phosphorus necrosis generally will be dealt with further on.

Commercial phosphorus is made from bone-ash by treating it with sulphuric acid, filtering and evaporating the product, heating this with charcoal, and afterwards distilling it. The substance known as white or yellow phosphorus was discovered as far back as 1669, by Brandt of Hamburg, and is, when pure, colourless and transparent, but when exposed to the light it becomes yellowish. During absorption of oxygen from the atmosphere it becomes phosphorescent. The greenish-white light thus evolved can at once be checked by such essential oils as turpentine and eucalyptus. The glow of phosphorus is an indication that oxidation is taking place, and that both phosphorous and phosphoric oxides are being formed, ozone being probably present at the same time. White phosphorus is extremely inflammable: it ignites at a temperature of 34° C., and forms with a plentiful supply of air phosphoric oxide P_{4}O_{10}, but if the supply of air is limited, phosphorous oxide is formed P_{4}O_{6}. It is with a paste made from white phosphorus that the ordinary strike-anywhere matches are headed.

Red or amorphous phosphorus, from which safety matches are made, has been known only since 1845. It was discovered by Schröter of Vienna, and is obtained by exposing ordinary phosphorus for some time in a closed vessel to a temperature of about 250° C. Red or amorphous phosphorus differs from yellow both physically and in other respects. It can be handled, for example, with impunity, and does not take fire when rubbed on any rough surface. It is non-volatile, and since it is not acted upon by the digestive juices of the alimentary canal it is non-poisonous. As much as an ounce of amorphous phosphorus has been given to animals without any bad effects, while one to three grains of the ordinary metalloid have caused death. In order to ignite red phosphorus, it has to be rubbed upon a surface that contains substances rich in oxygen. The heads of safety matches are composed of potassium chlorate and chromate, and other compounds that contain large quantities of oxygen, while the red phosphorus is present in the brownish-red layer that has been pasted on the side of the matchbox. It is significant of the habits of our countrymen that while sixty tons of white phosphorus are converted into the ordinary strike-anywhere matches every year in Britain, only three and a half tons of red phosphorus are required to satisfy the public demand for safety-matches.

White phosphorus is volatile at ordinary temperatures, and its vapour when pure is said by Schonbein to be odourless; the odour that is perceived is a mixture of ozone and phosphorous oxide. On analysing the fumes given off by phosphorus eight-tenths are found to consist of oxides of phosphorus.

Professor Thorpe found that when decayed human teeth were exposed to the fumes of phosphorus for twelve hours they lost 0.37 per cent. of their weight, and that carious teeth when crushed and exposed to a dilute solution of phosphoric acid (1 per cent.) lost 8.9 per cent. of their original weight. When, therefore, the fume of phosphorus co-operates with the saliva of the mouth, it must clearly exercise a solvent action upon the teeth. In the air of the dipping room of a match factory, Thorpe found O.02 milligrammes of phosphorus per 100 litres of air, while the same quantity of air of the boxing-room contained O.12 milligrammes of phosphorus. On analysing the water in which twenty-two of the workpeople had washed their hands, after working a certain number of hours in the factory, 37.3 milligrammes of phosphorus were found, or an equivalent of 4.2 milligrammes of phosphorus per person for each ten hours’ work.

The lucifer match industry of Great Britain and Ireland gave employment during 1898 to 4270 persons, of whom 1166 were males and 3104 females; about 1700 of these were working in phosphorus processes. Of persons under eighteen years of age there were 466 males and 1077 females. The match works were distributed as follows: in England and Wales 17, Scotland 2, and in Ireland 5, making a total of 24. Dr Whitelegge sends me the following information regarding the number of lucifer match works in January 1901--

Number in which yellow phosphorus is being used 15 Number in which the use of yellow phosphorus has been discontinued 3 Number not yet working 1 Number closed during past twelve months (one temporarily) 5 -- Total 24

The Chief Inspector of Factories, in his Annual Report for 1899, p. 318, states that the total cases of industrial phosphorus poisoning in this country within the last twenty years, of which there is a definite record, number 102. Before 1898 there were 92 cases of phosphorus necrosis, 6 in 1896, and 4 in 1899. Three other cases were reported in 1899, and are included in the return, but they did not reach the stage of necrosis. It has been urged with reason that such doubtful cases, when notified, should be placed on a “suspended” list, and judgment deferred until the diagnosis is quite clear. Of the 102 cases 19 terminated fatally. Dr Whitelegge informs me that three cases of phosphorus poisoning were reported during 1900; this brings the total number up to 105 in twenty-one years.

The ordinary lucifer match is dipped in a paste composed of glue, phosphorus, chlorate of potass, powdered glass, sometimes magnesia or lime, and coloured by a magenta dye. On an average there is 5 per cent. of phosphorus present in the paste, but sometimes it is double this amount. The paste or composition, when about to be used, is spread upon an iron slab kept at a moderate temperature. Into this paste the dipper, always a male in this country, quickly plunges the tips of prepared wooden splints that are projecting at a uniform level from a frame, and at once hands them over to a fellow-workman, who removes them to the drying chambers, which are ventilated by means of fans to renew the air, and to hasten the drying of the matches. At the distal end of the slab upon which the dipper heads the lucifers, there is, or ought to be, a fan towards which, when in operation, the fumes of the phosphorus as they rise from the paste can be seen travelling away from the face of the worker. Since the introduction of fans on the far side of the slab, the occupation of dipping in match works has become much less dangerous.

The boxing of matches, when done by hand, is attended by considerable risk to health, especially if the workroom is badly ventilated. In addition to the phosphorus fumes which pervade the boxing-room, the atmosphere is from time to time rendered more unhealthy by dense clouds of smoke given off by the matches that are frequently catching fire.

It was Lorinser of Vienna who first drew the attention of the medical profession to phosphorus necrosis, or disease of the jawbone, in lucifer matchmakers. This was in 1845, or about eleven years after the establishment of the match industry in Austria. Between the years 1839–1845 he had examined nine cases of phosphorus necrosis. Shortly after Lorinser had published his cases, Sir Samuel Wilks in our own country reported the occurrence of disease of the jawbone in a matchmaker, attended by suppuration, and followed by exfoliation of the bone. Since then in every country where ordinary lucifer matches have been made, the use of phosphorus has been followed by such an amount of ill-health and suffering on the part of matchmakers, that almost all the preventive measures which industrial science and legislation could suggest, short of total prohibition, have had a trial without rendering the industry completely safe. More than twenty years ago Denmark interdicted the use of white phosphorus, and the importation of ordinary strike-anywhere matches. France, several years after having made the manufacture of matches a Government monopoly, and having been obliged to pay large sums of money as compensation to the diseased matchmakers of Pantin-Aubervilliers, has commenced to manufacture matches from a harmless sesquisulphide of phosphorus; matches which, while possessing all the freedom from poison claimed for safeties, have the property of striking anywhere. Belgium has not only insisted upon the reduction of phosphorus in the paste to 8 per cent., but with the view of stimulating the manufacture of a satisfactory non-poisonous strike-anywhere match, has offered a prize of 50,000 francs (£2000). Holland[81] insists upon 5 per cent. of phosphorus in the paste, and allows no young person under sixteen years of age, and no woman to work in a match factory where yellow phosphorus is used. In Norway 28 cases of phosphorus necrosis occurred in fourteen years out of a total number of 600 workers. The match industry of Sweden gives employment to about one-twentieth of the artizan population. In the twenty-seven match factories of that country, 5500 persons find employment, males and females about equally. Although a large proportion of Swedish matches are safeties, yet as a matter of fact 80 per cent. of the matches produced are made from ordinary phosphorus. There is a large home consumption of strike-anywhere matches in Sweden. As a consequence of their manufacture, phosphorus necrosis is not unknown in that country, and on more than one occasion the question of the total prohibition of ordinary phosphorus has been discussed in the Rigsdag. Were such a thing to become law the match industry of Sweden, in the absence of an international agreement, would be seriously crippled. During the year 1891 there were 19 cases of phosphorus necrosis reported from thirteen factories. The Commission appointed by the Swedish Parliament to consider the prohibition of ordinary phosphorus did not feel justified in recommending such a sweeping change, believing that in better ventilation of the workrooms, repeated medical examination of the workers, and scrupulous attention to details in the various processes, the manufacture of matches could be robbed of much that had hitherto caused it to be regarded as a dangerous industry. Of the ninety match factories in Germany about thirty make ordinary lucifers. Several cases of phosphorus necrosis have occurred, but since the introduction of stringent regulations in 1884, requiring special ventilation, medical examination of the workers, personal cleanliness and separation of the workrooms, the amount of sickness has, within the last few years, materially diminished. In Austria-Hungary there are upwards of ninety match works. It is an important industry in Bohemia, Galicia, and Hungary. The matches chiefly find their way into Servia, Bulgaria, Roumania, and Turkey. In eighteen years 140 cases of phosphorus necrosis were reported to the Factory Inspectors; as many as 47 cases of phosphorus necrosis having occurred in the year 1888. This unhappy circumstance is to be explained by the fact that the manufacture of lucifers at this time was extensively but secretly carried on as a home industry. Experience has shown that this clandestine practice is always extremely dangerous. Fortunately the authorities have practically succeeded in abolishing this home industry. The regulations in Austria-Hungary resemble those of Germany. Switzerland in 1879 introduced a Bill for the prohibition of the use of yellow phosphorus, and two years afterwards it became law. Instead of abolishing phosphorus necrosis, however, the disease became not only more prevalent, but of a severer type, owing to the manufacture of matches as a home industry. As the interference of the Government defeated the object it had in view, viz., safe-guarding the health of the workers, the Act of 1879 was in a sense repealed. Whilst in Switzerland the importation and manufacture of matches made with yellow phosphorus is forbidden, the manufacture of lucifers is under the control of each canton, the Federal Council holding itself responsible for the conditions that are requisite for the health and safety of the workers, and also of the public.

Phosphorus Necrosis.--It is difficult to say what is the actual cause of necrosis of the jawbone in lucifer matchmakers. As to whether it is a primary lesion or one secondary to a general or constitutional form of poisoning, medical opinion is still divided. Most writers attribute the disease of the bone to the fumes of phosphorus, i.e. to the oxides of phosphorus, acting upon the decayed teeth of the workpeople. The fumes are supposed to penetrate a carious tooth and induce a periostitis or inflammation of the covering of the bone. The gum becomes swollen and painful. To such an extent has this been regarded as the explanation of the cause of necrosis that two of the large match works in this country had at their own expense appointed dentists to examine and keep in good order the teeth of the workpeople. Subsequently the Home Office, as a result of the opinions expressed at an Arbitration with the Match Manufacturers, decided to accept periodical examination of the teeth of the workpeople by a qualified dentist as a substitute for medical inspection. While regarding decayed teeth as a necessary preliminary to inflammation of the dental socket, Roussel holds that it is phosphoric acid that is the destructive agent. Gubler and Lailler,[82] on the other hand, maintain that they have met with phosphorus necrosis in the inferior jaw of a matchmaker whose teeth were perfectly sound, and that if phosphoric acid were the destructive agent the teeth ought to become softened and translucent. Gubler holds, but on what grounds we do not know, that it is phosphorus itself that penetrates into the soft tissues and destroys the nutrition of the covering of the bone. Under all circumstances “phossy jaw” is a painful affection, especially in the early stages, and although naturally it might be expected to occur with greater readiness in workpeople who are ill-nourished, scrofulous, or tubercular, yet I have seen it in male and female matchmakers who were physically strong and otherwise perfectly healthy. This circumstance, therefore, is rather in favour of phosphorus necrosis being in the first instance a local affection and primary. Once suppuration occurs, the painful tooth removed, and the pus thereby allowed to escape, pain is subsequently not a marked feature in the case. As the periosteum is usually separated, the affected portion of bone lying underneath dies and is exfoliated. A piece of bone varying from half-an-inch to three inches is thus thrown off. The process of separation of the bone by ulceration is extremely slow. It may extend over months or years if the bone is not surgically treated, and all this time there is a constant oozing of pus into the mouth of the patient, some of which must be swallowed along with the food, thereby undermining the health and causing anæmia or cachexia, or during sleep it may trickle down the throat into the respiratory passages and set up an unhealthy inflammation of the lining membrane, or it indirectly prepares the way for tubercular disease of the lungs. Either jaw may become necrosed. If anything, the inferior maxilla is more frequently affected than the superior. When the upper jaw is diseased there is a tendency for the inflammation to extend to the base of the skull and to induce a septic inflammation of the membranes of the brain, which is invariably fatal. In France both Dr Magitot of Paris and Dr Arnaud of Marseilles described a constitutional condition or cachexia in matchmakers to which they gave the name of phosphorisme, of which pallor, dyspepsia, albuminuria, and a tendency to bronchitis are the prominent features. Arnaud, with whom I had the opportunity of discussing this subject in Marseilles, found that as many as 28 per cent. of lucifer matchmakers, especially young women under eighteen years of age, suffered from bronchitis, but he did not think that matchmaking per se was a cause of tubercular lung disease, nor was it his experience that pregnant female matchmakers aborted more frequently than their sisters engaged in other occupations. Phosphorisme does not occur to any extent in English matchmakers. In visiting the match factories of Belgium, particularly of Grammont, where I met Dr Brocoorens, who from his large experience of industrial phosphorus poisoning had been invited to give evidence before the French Commission, my attention was drawn to the interesting fact that men who had been dippers and who had suffered from necrosis of the jawbone and recovered, exhibited an unnatural tendency to spontaneous fracture of their long bones, especially the femur. During twenty-five years in Grammont alone, which is not a large town, with six match factories giving employment to 1100 people, Dr Brocoorens treated 30 cases of fracture of the long bones, caused by muscular effort, in dippers who had previously suffered from necrosis of the jaw. This circumstance would rather suggest that in addition to the local disease of the maxillæ caused by phosphorus, there was also induced a wider spread morbid state, which was capable of showing itself long after recovery from the primary lesion. Spontaneous fracture of the long bones of matchmakers is not unknown in England. Dr Garman of Bow, medical officer to Messrs Bryant & May, informs me that he knows of nine cases in which the long bones of the arm and leg of matchmakers have become broken without any injury being received, and Dr Dearden of Manchester relates[83] the case of two dippers, “each of whom has had separately and at different times both thigh bones broken in a ridiculously simple fashion.” Dr Kocher of Berne had experience of a matchmaker who broke his thigh bone five times. These facts indicate that the osseous tissues of the body are in some way or other influenced either by phosphorus itself or its compounds, whereby they become unable to withstand external violence. Dearden is of opinion that the bones of match dippers contain an excess of phosphoric acid, which combines with the pre-existing neutral phosphate of lime to form a slightly acid salt. In this circumstance may possibly be found an explanation of the fragilitas ossium of lucifer matchmakers.

A brief notice of some experiments performed by Wegner may not be out of place here. He believes that phosphorus has a specific action upon bones, especially those of young animals. Wegner found that the administration of very minute doses of yellow phosphorus, ¹⁄₁₀ to ⅕ mgrm., for several weeks to young rabbits was followed by characteristic changes in the growth of the long bones, owing to the phosphorus acting as an irritant or stimulant to the bone-forming cells. Where loose cancellous bone was being formed from cartilage, phosphorus caused the deposition of a layer of dense bone, and if the drug was pushed a little longer, the soft, cancellous bone, formed before the phosphorus treatment was begun, became gradually absorbed. In this way the central or medullary cavity of the bone became enlarged, so that in the case of the long bones this cavity extended into the epiphyses or ends of the shafts. In other instances the newly-formed bone which had developed under the influence of the phosphorus, and also that which grows normally from the periosteum, became denser, so that in fowls Wegner found the medullary cavity obliterated by the deposition of hard bone. When lime salts were withheld from the food of the animals treated by phosphorus, the activity of the bone-forming cells continued, but no lime was deposited, and so there was produced a condition of bone such as is found in rickets. Kassowitz by similar means produced appearances closely resembling the soft and yielding bones that are met with in rickety children. Wegner, by exposing the bared tibia of an animal to the influence of phosphorus fumes, induced periosteal irritation and the deposit of new layers of bone.

Although it takes a long time for the sequestrum of a diseased jawbone to be thrown off in a person the subject of phosphorus necrosis, yet once it is expelled and the wound closed, the patient generally feels well enough to return to work in a match factory, and is placed in a department wherein he runs no further risk. Despite the tediousness and the unpleasantness of the malady, most of the patients recover. Dr Garman of Bow, treating his cases by the expectant method and allowing the sequestrum to be naturally separated, found that 83 per cent. of his cases recovered; Kocher of Berne prefers to remove by means of a surgical operation the affected portion of bone, and 83.7 per cent. of his cases recovered; while Kuiper of Jena, treating his patients on similar lines to Kocher, had 89 per cent. of recoveries.

This account of the diseases of bones of matchmakers allows us now to return to the original question, viz., the cause of phosphorus necrosis. Fume is generally regarded as the cause, but it is probably only an incident. In the pus that keeps oozing away from the necrosing jaw of an affected matchmaker, I have found numerous pus-forming micro-organisms, viz., putrefactive bacilli, streptococci and staphylococci pyogenes, and as Professor Stockman of Glasgow detected in addition in the pus a few tubercle bacilli, he is disposed to regard the “phossy jaw” of lucifer matchmakers as a true tubercular process. In several of the specimens of pus taken from the diseased jawbone of matchmakers sent to me by Dr Garman of Bow, I could find no trace of tubercle bacilli, although these were carefully searched for. The presence of the bacilli of tubercle in Professor Stockman’s specimens, which by the way I have had the privilege of examining and confirming, is an extremely interesting fact, and it certainly creates a bias in favour of the lesion being tubercular. On the other hand, the human mouth under all circumstances contains large numbers of micro-organisms, some of which are capable of becoming extremely virulent under altered conditions, and there is no reason why some of these might not find their way through a carious tooth to its socket in the jawbone or to the periosteum, where phosphorus fumes had previously gained entrance and set up irritation. In these tissues thus prepared microbes would find a suitable nidus for their multiplication. As the same remark applies to tubercle bacilli, it is clear that the final answer has not yet been given to the pathological problem of phosphorus necrosis. There is something in the causation of phosphorus necrosis that is still unknown to us, some peculiar action of phosphorus on the human subject that is not yet fully explained.[84] It is an extremely difficult thing to produce phosphorus necrosis in animals, either by exposing them to the fumes of phosphorus itself, or to clouds of smoke from burning matches.

In many instances where “phossy jaw” has occurred, the workpeople were at the time following their occupation, and had done so for many years. Acute phosphorus poisoning, practically speaking, does not occur in matchmakers. The poisoning is always chronic. Phosphorus necrosis was not recognised in Vienna until the industry had been established seven or eight years. The malady might have existed, and of course not been diagnosed. Most of the patients with “phossy jaw” whom I have seen had worked from seven to fifteen years at the trade, but the disease has been known to occur within twelve months after entering a match factory. Dr Garman has kept a register of all the cases of phosphorus necrosis that have occurred in Messrs Bryant & May’s for the last twenty years. During this period there have occurred 51 cases--31 females and 20 males. The upper jaw was affected fifteen times, and the lower sixteen, in the women: while in the men the numbers were eleven and nine. The severer type of the malady formed 70 per cent. of the cases in females, while in males, who as dippers are more exposed to the fresh fumes of phosphorus, it formed 85 per cent. Of these 51 cases of phosphorus necrosis nine ended fatally; 83 per cent. recovered and returned to work. On examining the register as to the ages at death, I find that these were nineteen, twenty-three, twenty-one, twenty-two, twenty-seven, twenty-seven, nineteen, twenty-two, and twenty-two years. Clearly, therefore, it is not necessary to have a very lengthened exposure to the fumes in order that a fatal result may follow. Co-existing pulmonary consumption was present in two of the patients, and doubtless contributed to the fatal ending. In Great Britain less than 1 per cent. of matchmakers suffer from phosphorus necrosis: in Switzerland it used to be 1.6 to 3, and in France formerly 2 to 3 per cent. Phosphorus necrosis, it is well to remember, does not always develop during the time an individual is following his employment in a match work; it has been known to occur two years after leaving the factory. The early age at which Garman’s patients died suggests that the vital resistance to the malady at this period is less than in later years.

Prevention of Phosphorus Necrosis.--Since the manufacture of lucifer matches is capable of inducing in the workpeople necrosis of the jawbone, which in the early stages is admittedly a painful affection, but fortunately one not often followed by any marked deformity, it is apparent that to the public must be given by the manufacturers some satisfactory assurance, if the use of yellow phosphorus is to be continued, that the industry which at present is harmful shall be converted into one that is free from danger. Is this event possible? Experience of match works, both at home and abroad, shows that where the industry is conducted on the best hygienic lines possible, phosphorus necrosis is practically unknown. This, so far as it goes, is satisfactory. It cannot be said, however, that the employment of white or yellow phosphorus can under all circumstances be rendered absolutely free from danger. The education of the working classes to use only safety matches would of itself very largely diminish the danger by reducing the demand for ordinary strike-anywhere matches. Dipping of the wooden splints in cold composition instead of hot would, as in the case of vestas, in the manufacture of which “phossy jaw” does not occur, also tend to diminish the ill-health of the workers. It has been demonstrated that certain essential oils are capable of checking the oxidation of phosphorus, which is one of the possible causes of phosphorus necrosis. It has, therefore, been recommended to circulate the vapour of turpentine through the dipping and boxing rooms. In some American factories the workpeople wear suspended round their necks small vessels containing turpentine. Of all hygienic measures full and free ventilation is the best. Years ago the scourge of matchmakers in Belgium was “phossy jaw,” but shortly after the introduction of hygienic measures and the reduction of phosphorus to 8 per cent. in the paste, there was observed a very notable declension in the number of cases of necrosis, and in our own country the removal of phosphorus fume by powerful aspiration from the dipping slab, frequent renewal of the air of the drying chamber, and ventilation of each of the benches at which the boxing is done by women by hand, have exercised an undoubted influence in preventing phosphorus necrosis. Periodical examination of the teeth of matchmakers by a dentist, with the necessary local treatment, including temporary suspension from work on the detection of disease in the early stages, will be beneficial. It is one of the requirements of the Home Office that this dental examination shall be periodically made. Whether of itself it is sufficient to permanently obviate the necessity for a medical examination of the workers by a doctor in addition remains yet to be seen. Since the frequent firing of matches is a cause of pollution of the atmosphere of the boxing-room, and filling of the matchboxes by hand brings the worker into direct contact with dried phosphorus paste, it is advisable to discontinue the practice of cutting wooden matches once they have been headed, and to substitute machinery for all hand labour, which, as in the case of the Diamond Match Company, Liverpool, dips, dries, and boxes the matches in large and well-ventilated rooms, and has thereby practically made lucifer matchmaking a harmless industry. It is absolutely necessary that personal cleanliness should be attended to, and that there should be adequate provision of washing appliances with hot and cold water, plenty of soap and towels, that overalls should be worn, frequent change of occupation from one department in the factory to another, and that no food should be allowed into the workroom.

Can any substitute be found for yellow phosphorus, capable of producing a non-poisonous match that will strike anywhere, and yet conform to the same conditions as ordinary phosphorus? France has, within the last three years, ceased to manufacture matches from yellow phosphorus. In that country the manufacture of matches is a State monopoly. A short while ago the Government felt itself obliged to change the method of manufacture, partly on humanitarian grounds, but very largely owing to the numberless claims for compensation by the workpeople upon the Minister of Finance. In the match works at Pantin-Aubervilliers, there were, in 1894, 32 cases of phosphorus poisoning, 125 in 1895, and in 1896 the number rose to 223, or one-third the effective force of the factory. Many of these must have been of a mild nature, and probably some of them were cases of imposition, for when analysed carefully it would appear that between 1888 and 1896 there were eight cases of deforming necrosis, 12 of necrosis requiring surgical treatment, 21 probable cases of phosphorus necrosis, and 18 of phosphorisme, making a total of 59. At this time the match paste, in addition to lead, contained often as much as from 20 to 30 per cent. of phosphorus. From the 1st January to 31st December 1896, the State paid 400,000 francs as allowances to sick-workers, men and women, employed at Pantin-Aubervilliers, or an average of 650 francs per head employed. It was in consequence of this experience that in order to encourage research, which would lead to the manufacture of a non-poisonous match, the State granted financial help. After many experiments--such, e.g., as the matches of M. Ponteau, made from acetate of amyl, during the manufacture of which a splitting headache, a feeling of cerebral fulness, and a throbbing of the head were complained of by the workers, a circumstance that led to their manufacture being abandoned; also the lucifers of M. Miram, which met with a similar fate, since they contained lead, and therefore one poison was simply being substituted for another,--the French Government at present believes that in the substance known as sesquisulphide of phosphorus it has found an answer to the question raised at the head of this paragraph.

The toxicity of the sesquisulphide of phosphorus is small. Messrs Sevène and Cahen gave repeated doses of 3 centigrammes (⅖ grain) of the substance daily to guinea-pigs without these animals appearing to suffer, although the ingestion of 3 milligrammes (¹⁄₂₅ grain) of white phosphorus caused rapid death. The dose of 3 centigrammes (⅖ grain) to a guinea-pig would correspond to 3.5 grammes (54 grains) for a human adult, that is to say, to the amount of sesquisulphide of phosphorus present in 6000 matches. For these and other reasons based upon experience, the French inventors maintain that sesquisulphide of phosphorus matches are harmless. The following is the composition of the paste employed:--

Sesquisulphide of phosphorus 6 Chlorate of potass 24 Zinc white 6 Red ocre 6 Powdered glass 6 Glue 18 Water 34[85]

The sesquisulphide is almost inodorous as a powder, and is non-poisonous. When matches are headed with a paste made from it, they are capable of striking anywhere. The only impurity which the sesquisulphide can contain is some red or amorphous phosphorus. At first manufacturing chemists expressed doubtful opinions as to the keeping properties of the matches, also as to their capability of being transported across the seas, and of remaining good in all climates. Two years’ experience of the manufacture of matches from sesquisulphide of phosphorus has demonstrated such fears to have been groundless. Dr Courtois-Suffit, the Medical Inspector of the Match Works at Pantin-Aubervilliers, says that “since substituting sesquisulphide for yellow phosphorus, not only have the workpeople been more healthy, but that there has been no complaint on the part of the consumers.” No match is superior to the lucifer made from yellow phosphorus. French matches have never been regarded as equal to those of English manufacture. France is not an exporting country. While, therefore, the introduction of what is called a sans phosphore match in France has answered satisfactorily, it does not follow that the manufacture of this particular kind of lucifer is the best for all countries, and especially for such a large exporting country as Britain.

In Italy the same subject has received the attention of scientists. M. Bertarelli,[86] in a lecture at the University of Turin, demonstrated the properties of a non-poisonous match made by Dr G. Graveri of Villanova-Sollaro, the principal ingredient of which is persulphocyanic acid, a substance obtained from the residue of gas-works, of a yellow colour, crystalline, soluble in alcohol, ether, and boiling water, decomposing at a temperature of 220° C., and giving rise to sulphide of carbon, ammonia, and sulphur. This is made into a paste with sulphur and antimony trisulphate. The matches ignite when rubbed briskly upon a rough surface, and no cyanogen is evolved. Bertarelli states that he has given to dogs for several days 3 to 4 grammes (46 to 60 grains) of the paste used for heading the matches, and beyond slight vomiting he has not noticed any accident, whilst 0.7 grammes (11 grains) of ordinary phosphorus paste caused death. It is claimed for his matches that they cost less to produce than ordinary matches, they ignite noiselessly, and develop no odorous gases, that they are non-hygroscopic and non-poisonous. The only drawback is stated to be the escape of hydrochloric acid fume during their manufacture, but this can be overcome by efficient ventilation.

Great Britain is not only a consumer but a large exporter of lucifer matches, and it is this circumstance that raises a difficulty in regard to the total abolition of the use of yellow phosphorus in this country. If other matchmaking and large exporting countries, such as Belgium, Sweden, the United States, and Japan, could come to some satisfactory terms of international agreement with Britain not to manufacture lucifer matches from yellow phosphorus, the question would be settled, if not permanently, at least for a time. It would be useless for Britain with her free trade to abolish yellow phosphorus, thereby crippling her own matchmaking industry, and at the same time allow matches made from the poisonous phosphorus to be imported from other countries wherein Government supervision is perhaps less strict than in ours. Such a course would only transfer phosphorus necrosis from our own to other countries. English methods of manufacture, like national customs, die hard. It is pleasing to observe, however, that the objection on the part of British match manufacturers to the use of substitutes for yellow phosphorus is gradually disappearing. Messrs Bryant & May no longer use yellow phosphorus. Mr Gilbert Bartholomew, the Managing Director of the firm, in answer to some queries I addressed him (1901), informs me that “we are well satisfied with our long trial of the new composition. There has not been, and there cannot be, from the nature of the composition, any sickness among the workpeople. We have not used an ounce of yellow or poisonous phosphorus for nearly ten months.... We do not think there is an increased demand for safety matches; the great demand is for strike-anywhere.” It is gratifying to know that some of the smaller firms of lucifer matchmakers have also undertaken to produce ordinary strike-anywhere matches from a non-poisonous substance. How far these non-poisonous substances are quite free from danger and as sources of irritation, remains to be seen, for conjunctivitis, œdema of eyelids, and eczema have been noticed in the workers.[87]

Treatment of Phosphorus Necrosis.--It is unnecessary to enter into this at any length. Such preventive measures as a medical and dental examination of the workpeople before entering the factory, and from time to time afterwards, combined with suspension when necessary, personal cleanliness, and the use of terebinth gargles, wearing of overalls, and a change of employment in the factory, also thorough ventilation of the workrooms and of the dipping tables by reliable artificial means, will, if carefully carried out, do a very great deal to make and keep the workpeople healthy.

Once phosphorus necrosis has developed, it may either be treated by antiseptic mouth-washes, maintenance of the general health by good nourishing food, and a life spent in the open air, thus allowing time for exfoliation of the necrosed bone to take place naturally, a process which, as we have seen, may extend over many months; or it may be treated surgically by removal of the piece of diseased bone. Each method has its advocates, but the results are practically the same, viz., upwards of 80 per cent. of recoveries.

THOMAS OLIVER.

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XXVIII. DANGERS IN THE USE OF MERCURY AND ITS SALTS

Introduction.--The number of industries and the number of persons coming into contact with mercury in this country is not large. Probably not more than 500 to 1000 persons are exposed to the danger of industrial mercurial poisoning in Great Britain, but no matter how the metal or its salts are used, those handling it run considerable risk. In some industries, indeed, as, for instance, the silvering of mirrors with an amalgam of tin and mercury, which was for over a century the great source of mercurial poisoning, the matter is now only of historical interest, as the process in question has been replaced within the last twenty years by an innocuous one in which mercury is not used. On the other hand, fresh industries arise in which the metal is used, as, for example, the manufacture of electrical meters and incandescent electric lamps.

Historical.--As far back as the year 1665, in the Philosophical Transactions of that year, a reference is made by Dr Walter Pope to the tremor affecting the hands of a worker in some cinnabar mines in Italy. In 1721 Antoine de Jussieu[88] described the symptoms of salivation, ulceration of the gums, and tremor which affected the workers in the quicksilver mines of Almaden, in Spain. In the various translations of Bernardino Ramazzini’s work, De morbis artificum diatriba, originally published in 1702, an account is given of the effect of mercury on miners and gilders.

One of the first references to the occurrence of mercurialism in the process of silvering of mirrors was made by Bateman[89] in 1812, but the great work which still remains the classical work on the subject of chronic industrial poisoning, due to mercury, was published in 1861 by Adolf Kussmaul,[90] Professor of Medicine in Erlangen. The splendid use which he and other medical men made of the opportunities offered them of studying the clinical symptoms among persons employed in the silvering of mirrors in Fürth and Nuremberg, the principal seats formerly of the industry on the Continent, and the publication of their observations, led up to the introduction of the stringent regulations which have since caused the process to be given up.

In 1829, Dr Reitz[91] of St Petersburg published an account of the danger to health in hatters furriers’ processes in that city, and showed that the solution (regarded then as it still is as a secret), contained mercury, arsenious acid, and nitric acid.

He does not particularly refer to the occurrence of tremor, but describes the death of three men from acute bronchitis after mixing the nitrate of mercury solution.

Industries in which Poisoning may occur.--The industries in which mercurial poisoning may occur are:--

1. Recovery of the metal from the ore.

2. Separation of gold and silver from their ores by means of an amalgam with mercury.

3. The manufacture of barometers and thermometers and other philosophical instruments.

4. The manufacture of incandescent electric lamps, where mercurial pumps are used to create a vacuum.

5. The manufacture of electrical meters.

6. Gilding and silvering, generally known as water-gilding: where an amalgam of gold or silver is applied to the objects, and the mercury volatilised by heat.

7. Chemical works: where pharmaceutical mercurial preparations are made.

8. Paint and colour works: where anti-fouling paints or vermilion are made.

9. In hatters furriers’ workshops: from the brushing of rabbit skins with an acid solution of nitrate of mercury.

10. Bronzing with a solution of nitrate of mercury: as in bronzing the inside of field-glasses.

In the first six the poisoning takes place almost entirely through the inhalation of mercurial vapour, and hardly at all from dust; in (7) it may arise either from vapour or from, as is the case in (8), contamination of the hands and subsequent ingestion of the salts; in (9) it results from the inhalation of fumes or the ingestion of particles of fur impregnated with nitrate of mercury.

Other processes which deserve mention as a possible source of mercurial poisoning are: electrical engineering, mercury being used in amalgamating zinc plates; taxidermy when corrosive sublimate is used; the manufacture and use of fulminate of mercury in explosive factories; sole-stitching by the “Blake sole-stitching machine,”[92] in which mercury is used to prevent the escape of gas.

Mode in which Poisoning is brought about.--Mercury in the liquid form, even when swallowed in large amount, rarely gives rise to poisoning. When absorbed in the form of vapour it frequently does, but it would be wrong to suppose that the vapour can as such pass through the lining walls of the alveoli of the lungs. It must first undergo condensation, and the tiny globules so formed become oxidised and then dissolved. In view of the fact that expired air is warmer than that inspired, it is difficult to see where this condensation takes place. Von Renk[93] carried out a series of experiments to see whether the mercury that was scattered in rooms where the silvering of mirrors was carried on could be swallowed with the dust. He found, however, such small quantities of dust in the air (only 7.3 milligrammes in 712 litres of air) that he concluded absorption of mercury in this way was improbable. On the other hand, mercury gives off vapour at ordinary temperatures, the amount depending on the vapour tension, and he found appreciable quantities (2 milligrammes) in a cubic metre of air in a room without special ventilation immediately above a layer of mercury half a square metre in area. As in eight hours a worker inhales and expires about 3 cubic metres of air, if the air breathed were charged only to an extent of 1.5 milligrammes per cubic metre, it would mean that 4.5 milligrammes entered the lungs. Were this continued day after day, injurious effects would necessarily ensue.

The reactions which enable mercury to enter the circulation are only imperfectly understood. It is acted on more readily by salt solution than by dilute acids. The presence of both salt solution and free acid must favour greatly the solution of the metal. Corrosive sublimate forms an albuminate with albumen insoluble in water, but readily soluble in the presence of salt solution. In this remarkable reaction of the solubility of albuminate of mercury in presence of sodium chloride lies the probable explanation of the occurrence of mercurial poisoning.[94]

Symptoms.--Although in industrial mercurial poisoning the symptoms occasionally resemble those which result from the internal administration of full doses of mercury, such as excessive salivation, swelling and ulceration of the gums with fœtor of the breath, followed in severe cases by looseness and falling out of the teeth, they are as a rule much slower in their onset and more insidious in character. For years the only sign may be more or less gastric disturbance, a gradually increasing anæmia, a slight increase in the secretion of saliva with tendency to ulceration of the gums, and slight tremor of the muscles of the face and hands, accompanied by a certain amount of nervousness.

Kussmaul, from his wide experience among the silverers of mirrors in Fürth, describes three stages in industrial mercurial poisoning: first, erythism or psychical changes; secondly, tremor; and thirdly, the final or cachectic; and my own experience points to the correctness of his description.

The first commences usually in the digestive tract with slight stomatitis and salivation. The worker becomes pale and loses his appetite. He frequently has headache, giddiness, and transitory pains in the limbs. The muscles of the face twitch, the fingers tremble when spread out, and the tongue is also tremulous when protruded. The mental condition undergoes change. Workers assured of their skill become shy and nervous, especially when watched. Sleep is often interfered with and broken by nightmare. Sometimes the tonsils and pharynx become involved in the inflammatory processes affecting the mouth.

At this stage if the employment be given up, the symptoms disappear in about three weeks. If not, the weakness of the muscles increases. Palpitation, headache, sleeplessness, and emaciation all become worse.

In the second stage of tremor, disturbance of the muscular system preponderates. It is observed principally in the muscles of the face, hands, and arms; more rarely in the legs. At first it may amount only to slight tremulousness, but gradually it advances until the movements become convulsive in character, and the hand cannot be directed with certainty to any particular object. The speech, from involvement of the muscles of articulation, becomes slow and indistinct. The psychical condition changes to one of depression or despondency. There may be hallucinations, loss of memory, and dulness of the intellectual faculties. In women, menstruation is diminished or ceases. Miscarriage is frequent, and the offspring is liable to be the subject of rickets or scrofula.

The condition of the teeth of persons exposed to the fumes of nitrate of mercury in hatters furriers’ processes deserves separate mention. The typical appearance in the teeth of those who are engaged in “carotting,” that is, brushing the rabbit skins with the dilute acid solution for several years, is loss of the molar teeth in the upper and lower jaws. The upper incisor and canine teeth are not infrequently absent, and such teeth as remain (generally the lower incisors and canines) are characteristically blackened and often loose. They show a marked tendency to erosion (a process quite distinct from caries, as the enamel and not the dentine suffers most) from the acid fumes, and frequently the gums recede, so that the anterior surfaces of the roots are exposed.

Chronic mercurial poisoning does not frequently lead directly to death. It appears to lower the vitality of the tissues markedly, and Kussmaul calls attention to the frequency with which mercurial workers die of phthisis.

Recovery from the Ore.--The principal ore from which the metal is obtained is cinnabar, or sulphide of mercury. It occurs principally in Idria in Illyria, where the greater part of the male inhabitants are concerned with its extraction, in Almaden in Spain, and also in China, Peru, California, and in smaller quantity in some of the German States.

The extraction of the metal depends on the principle that by heating the ore in the presence of air, oxidation of the sulphur present results, while the mercury is liberated in the form of vapour, which is condensed in suitable flues kept constantly cool by a stream of water. Complete condensation of the vapour is difficult.

In the actual mining of the ore, poisoning does not occur. Danger principally attaches to the smelting operation, to the cleaning out of the flues, and to the packing of the quicksilver.

The amount of illness caused may be judged from the fact that between the years 1879–1884, of 1000 workers, 112 suffered from mercurialism, although this figure does not take account of gastric symptoms, which, if included, would raise it to 200 or 250 per 1000.[95]

The dangers can be best avoided by suitable arrangement of the furnaces so as to prevent the escape of fumes, the wearing of overalls, and ample provision of washing and bath accommodation.

Making of Thermometers.--In the making of thermometers a small funnel is blown on the top of a capillary glass tube and filled with mercury. Heat from a spirit lamp or gas jet is applied to the bulb, and the expanded air partially escapes. On cooling, a portion of the mercury passes into the bulb to take the place of the air which has escaped. This process is repeated until the bulb and part of the tube are full of mercury. The mercury is then heated to boiling, mercury vapour escapes, carrying with it the air and moisture which remain in the tube. The tube, when full of the expanded mercury and mercury vapour, is hermetically sealed at one end.

The number of persons employed in the industry of thermometer and barometer making is small. They generally describe themselves as experimental glass-blowers. The processes are usually carried on in small workrooms, the conditions in which, owing to the wooden benches and floors affording lodgment in the crevices for particles of mercury and to the gas jets alight at every bench, are not conducive to health. Close observation of almost every worker who has been employed for a few years (and when once entered on it is rarely exchanged for another), reveals the presence of chronic mercurialism either in slight tremor of the muscles of the face or hands, or the characteristic earthy complexion.[96]

Incandescent Electric Lamps.--In the manufacture of incandescent electric lamps, if mercurial pumps are used to produce the vacuum in the glass envelope, the danger from the scattering of mercury, which not unfrequently happens through breakage and careless manipulation, is considerable.

In Berlin and Buda Pesth[97] several cases of chronic poisoning from this source occurred a few years ago. The industry, so far as the operations in the pump-room was concerned, was placed under special regulations in Berlin, requiring (1) mechanical ventilation; (2) overalls and head coverings for the persons employed; (3) provision of a meal room and the washing of hands and face with soap, and the rinsing out of the mouth with potassium chlorate before meals; (4) a warm douche bath three times a week; (5) medical examination of the workers once a week. The effect of these regulations was a cessation almost at once of mercurial poisoning, and they soon led to the introduction of mechanical pumps to replace those of mercury.

In this country no case has been reported in this industry, and the evidence I have found so far of mercurialism among the workers is slight.

Electrical Meters.--The same dangers from the free use and handling of mercury is to be found in workshops where electrical meters are made, and they can only be satisfactorily met by the adoption of the precautions mentioned in the last section of this chapter.

Gold and Silver Extraction.--Both gold and silver are occasionally separated from the ores in which they are found by amalgamation with mercury, the latter subsequently being removed by distillation.

Water-gilding.--In the gilding and silvering of ornaments, the use of mercury has fortunately been almost entirely replaced by the much less harmful electroplating. The gilding, however, produced by the amalgam with mercury and subsequent firing (water-gilding) is more durable than that obtained by electroplating, but such articles as military buttons are still prepared in the old dangerous way, although greater precautions are taken to see that the fumes are carried away. The object to be gilt is treated with a solution of nitrate of mercury, and the amalgam (previously prepared by heating an alloy of gold with silver and copper to redness, adding an eighth part by weight of mercury, subsequently cooling in water and expressing any excess of mercury) is applied with a brush. Formerly the article was heated over a charcoal fire, with, necessarily, escape of fumes both of carbonic oxide and mercury into the room. Now it is done either in a closed stove or on a gas jet with a good draught.

Silvering of Mirrors.--The process of silvering of mirrors, which formerly caused so much suffering, was to spread out on a perfectly horizontal table of marble or glass a sheet of tinfoil. On to this a small quantity of mercury was poured to form an amalgam. A large quantity of the metal was then added, and the carefully polished plate of glass was slid over it, pushing some of the excess of mercury in front, which was collected in small channels, but abundance remained in the cracks and crevices of the tables. Heavy weights were placed on the glass to press out the mercury, and in a few days the combination of mercury and tin was found to have adhered firmly to the glass.

It may be well to refer here to the process which has taken its place. The method is a wet one, and consists in pouring over the cleaned and dried glass plate a solution of nitrate of silver, containing an alkaline reducing agent, such as a tartrate, or more commonly ammonia. A reddish or black precipitate at first falls down, and later on a shining surface of metallic silver holds close to the glass. The glass is then carefully wiped dry and backed with a coat of varnish or red lead. Cases of lead poisoning have occurred from the use of red lead in this way.

Statistics of Dr Wollner[98] show that in 1885, on an average, 160 persons were engaged in the silvering of mirrors in Fürth. Among these there were 165 illnesses (103 per cent.) for which sickness insurance money was paid, and of these 60.6 per cent. were on account of mercurial poisoning. The percentage among males and females was practically the same, but the number of sick days was greater in the case of men than in that of the women--66.7 days as compared with 50.5.

In 21 per cent. symptoms became prominent in from one to two years, in 61 per cent. in two to six years, in 15 per cent. in six to ten years, and in 3 per cent. in ten to seventeen years.

In 1898 the Factory Inspector for the district of Fürth states in his report that only seven persons were engaged in the process, and that their employment was intermittent. As the process has thus become practically extinct, it is hardly necessary to give the regulations enforced in Germany since 1889, but they are well worth reading by those who are anxious to bring to an end particularly dangerous industries, especially when they are carried on in the homes of the workers.

Hatters Furriers’ Processes.--Mercury in the form of a dilute solution of the nitrate is used in the preliminary process of felt hat making to increase the felting properties of the rabbit fur. The industry employs in the mercurial process alone between two and three hundred men and women. After the longer hairs have been removed by fur pullers, the rabbit skins are subjected to a process known as “carotting,” in which they are brushed with the above solution. When dried they are brushed by machinery to loosen the fur, and then each rabbit skin is passed through an ingenious machine with rotating knives so arranged as to cause the skin to be shaved off in strips, leaving the fur intact.[99]

Few combinations can be imagined more likely to affect detrimentally the health and more particularly the teeth of workers than that of mercury and nitric acid. As might be expected, those engaged in “carotting” show in most marked degree injury to the teeth from the nitric acid fumes, the typical condition of which has already been described, while tremor and erythism predominate in those engaged in the later processes as the result of the inhalation of particles of fur impregnated with the nitrate of mercury.

The following figures make this clear, giving the result of an examination made by me of 111 persons in eight different factories, who had worked for one year and upwards--

+---------------+---------+-----+-----+-----+-----+-------+-----+ | Process. | Number |Teeth|Per |Teeth|Per |Tremor.|Per | | |examined.|Bad. |cent.|Fair.|cent.| |cent.| +---------------+---------+-----+-----+-----+-----+-------+-----+ |Carotting | 30 | 20 | 66.6| 10 | 33.3| 1 | 3.3| |Other processes| 81 | 27 | 33.3| 54 | 66.6| 17 | 21.0| +---------------+---------+-----+-----+-----+-----+-------+-----+

A “fur” as received from the cutting machine, analysed in the Government Laboratory, was found to contain 1.34 per cent. of nitrate of mercury. The mercury forms a very insoluble combination with the keratine in the hair which is not removed in the subsequent processes of felt hat making. Jungfleish[100] found in a layer of felt which had been deposited on the revolving cone used in making hats nearly 0.5 per cent of metallic mercury, and in a felt hat which had been worn for a long time 0.7 per cent. Nevertheless, mercurial poisoning even of slight degree does not occur, or at any rate only very exceptionally, in the later processes of felt hat making.[101]

Preparation of Mercurial Compounds.--In factories where mercurial compounds are made, such as calomel, corrosive sublimate, the red oxide (largely used as an anti-fouling paint for ships’ bottoms), and vermilion, there is considerable evidence of mercurial poisoning among the workers. For instance, of 27 men so employed, I found in four (15 per cent.) more or less salivation, and in ten (37 per cent.) tremor, besides such other symptoms as anæmia and gastric derangement. Danger arises from the volatilisation of the metal in the subliming operations, and also to some extent from the dust which, though very heavy, can become scattered, if such processes as mixing, sifting, and grinding are not carried out with care in closed-in vessels.

Calomel, subchloride of mercury (HgCl), is made either by intimately mixing corrosive sublimate with metallic mercury and subsequent sublimation, or by mixing definite proportions of mercuric sulphate, metallic mercury, and common salt. The mixture is then heated so that the calomel may pass off as vapour and be condensed in the cool subliming chamber. Finally, it is ground wet, dried, and sifted. All these later stages in the preparation must be carried on in a closed apparatus, and with observance of great care.

Corrosive sublimate, the bichloride of mercury (HgCl_{2}), is made by heating two parts by weight of mercury with three parts of strong sulphuric acid. To the mercuric sulphate so formed when dry, one and a half parts of common salt are added. The corrosive sublimate is converted into vapour by heat, and condenses on the upper cooler portion of the vessel in lustrous colourless masses, leaving a cake of sulphate of soda below. The sublimate is then scraped out, and usually undergoes no further treatment such as grinding. The operation of sublimation requires very constant attention on the part of the worker to prevent the vessels in which the vapour sublimes being overheated, and so allowing its escape.

In the preparation of red oxide of mercury, nitrate of mercury is first made, in which care has to be taken that the fumes so developed are carried away by ventilating shafts in connection with each vessel. The crystals formed after evaporation are ground with addition of metallic mercury, and then heated in an oven. Nitrous fumes are evolved, and the oxide, black when hot, turns to a brilliant red crystalline powder on cooling. Finally, it is ground wet, dried, and sifted.

Vermilion, sulphide of mercury (HgS), is made by mixing excess of sulphur with metallic mercury in closed rotating wooden drums. Black amorphous sulphide of mercury results,[102] which on heating to 150° C. becomes converted into a dark violet powder. From this vermilion is obtained by sublimation, a process attended with risk from escape of vapour. Finally, it is ground wet, and according to the fineness of the grinding so is the particular shade of colour obtained.

The manufacture of calomel, corrosive sublimate, and vermilion can be made by a wet method throughout without danger, provided reasonable care is taken.

Preventive Measures.--The conditions to be aimed at in places where metallic mercury is handled (and for the most part also in places where salts of mercury are used), are as follows:--

1. The flooring and benches should be smooth, impermeable, and free from cracks or crevices in which mercury can lodge. Preferably the floor should be of some kind of asphalt or cement, laid in such a way that channels all converge towards a receptacle where the scattered mercury may collect. Wood, although at present in common use, is not well adapted for the purpose. The receptacles should be covered over, leaving only a narrow opening for the mercury to run in.

2. There should be ample light, and the windows of all rooms where mercury vapour may be produced should preferably face the north.

3. Mercurial processes should be carried on in rooms separate and distinct from the other workrooms.

4. Any unnecessary raising of the temperature above 60° F. is to be avoided, and consequently there should be no direct heating of the rooms by open fires or stoves.

5. Mechanical ventilation should be provided, and reliance not be placed merely on differences of temperature between the outside and inside air. Inlets for air should be above the level of the heads of the workers, and the draught of the fan should be a downward suction one.

6. Workers should wear overalls and head coverings.

7. Shortness of the hair, shortness and cleanliness of the nails, a proper hygiene of the mouth, and baths, would do much to protect the workers. Ample washing convenience, including soap, nail brushes, and towels, should be provided.

8. Meals should be prohibited in any room where mercury is handled.

9. Periodical medical examination, with power to the surgeon appointed to suspend temporarily or permanently from work.

* * * * *

In two of the largest factories in which mercurial preparations are made, in addition to the carrying out of all dusty processes such as mixing and sieving, as far as possible, in a closed-in apparatus, the following measures have been taken:--

RULES TO BE OBSERVED IN THE MANUFACTURE OF MERCURIAL PREPARATIONS.

1. The firm will appoint a surgeon to examine all persons employed in mercurial processes at least once in every month, and he will undertake any necessary medical treatment of illness contracted in consequence of such employment. He will have power to suspend any such person from work in any place or process.

The surgeon will enter in a register the dates and results of the examination of the person employed as above. No person after suspension can be employed in any mercurial process without written sanction from the surgeon.

Every person employed in a mercurial process must present himself at the appointed time for examination by the surgeon.

2. The firm will provide sufficient and suitable overall suits for the use of persons engaged in the processes of sifting and grinding, and every person when so engaged must wear an overall suit.

3. The firm will provide respirators approved by the surgeon for persons engaged in processes where there is unavoidable dust, and every person so employed must wear the respirator.

4. The firm will provide and maintain washing conveniences in the proportion of one lavatory basin to each five persons employed, with soap, nail brushes, and towels, and a constant supply of hot and cold water laid on to each basin.

Every person must, before meals and before leaving the premises, thoroughly wash in the basins provided, and those who have worn overalls and respirators must deposit them before leaving the factory after the day’s work in the place appointed for the purpose by the firm.

The firm will see that the overalls are washed once a week, and the respirators renewed or washed every day.

5. The firm will provide and maintain a bath with hot and cold water laid on, and a sufficient supply of soap and towels. Every person shall have the opportunity of taking a bath at the factory once a week, and those whom the surgeon directs must do so.

Each person taking a bath must sign his name in a register.

6. The firm will provide and maintain a cloak-room in which workers can deposit clothing put off during working hours, separate from any portion of the works where mercurial processes are carried on.

7. No food or tobacco are to be taken into, nor is food to be eaten in any part of the factory where mercurial processes are carried on.

8. The foreman must report to the manager any instance coming under his notice of a workman neglecting to observe these rules.

Note.--The danger against which the rules are directed is that of mercurial poisoning, of which the principal symptoms are soreness of the gums, offensive breath, increase in the amount of spittle, and trembling of the fingers. Workers are warned of the danger arising from the chewing of tobacco, and of eating food with unwashed hands. Mercury has a tendency to destroy the teeth, and this can be best obviated by the use of a tooth-brush once every day.

In hatters furriers’ processes the remedial measures required are rather different, although suggestions (6), (8), (9), and part of (7) equally apply. It is necessary in this industry to remove the fumes arising from the solution of nitrate of mercury in carotting, and to secure the absence of dust at the cutting machines, either by perfecting the machinery and fittings of the receptacles into which the bulk of the dust is carried by the revolving knives, or by increasing this draught by means of a fan. This latter mode has been adopted with success both as regards removal of dust and economy of work. It is desirable, too, that the primitive stoves at present in use for drying the “carotted” skins should be replaced by the kind now commonly to be found in steam laundries, of “horses” sliding in and out of the heated chamber on rails.

By the French law of 13th May 1893, the treatment of the skins and fur of hare and rabbit skins with nitrate of mercury is scheduled, with others, as an industry in which neither children nor females may be employed.

T. M. LEGGE.

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Chapter XXIX

THE LESIONS RESULTING FROM THE MANUFACTURE AND USES OF POTASSIUM AND SODIUM BICHROMATE

Peculiar lesions--erosion of the septum of the nose and the production of ulcers on the skin--are caused by bichromate of potassium or sodium. Erosion of the septum is found only among persons engaged in the manufacture of the salts, but ulceration of the skin of exposed parts, principally the hands, although most severe and most frequently met with among the same class of operatives, may be detected among persons engaged in the many industries in which the salts are used in solution.

Bichromate of potassium and sodium, commercially known as “bichromes,” are used largely--

1. In the manufacture of colours, such as the various chrome yellows, by the interaction of lead acetate and bichromate of potassium.

2. In dyeing and calico-printing. In dying cotton yarn the material is soaked in lime water, and, after wringing, is transferred to a vat containing lead acetate. It then passes through a solution of bichromate which develops the yellow colour on the fibre.

In calico printing potassium bichromate is used in the indigo blue discharge style, when it may be printed from a paste containing 40 per cent. of bichromate, which will discharge the colour from the blue material after suitable treatment. Or it may be used for the production of chrome lead colours by first printing the desired pattern on the calico with a paste containing acetate of lead, and subsequently passing this through a 2 to 5 per cent. solution of bichromate.

Potassium bichromate is the most important mordant for wool. The mordanting bath is prepared with 2 to 4 per cent. potassium bichromate (of the weight of the wool) and the necessary quantity of water, amounting to from 50 to 100 times the weight of wool.[103]

3. In photography. The carbon process depends on the fact that gelatine and potassium bichromate combine under the influence of light to form a compound which is insoluble in hot water. The strength of the bichromate solution for this process does not exceed 5 per cent.

4. As an oxidising agent for the manufacture of coal tar colours, for the bleaching of oils, etc.

The first full account of the lesions arising in the course of the manufacture of bichromate was given by Bécourt and Chevallier in 1863.[104] In 1854 Heathcote published in the Lancet[105] an account of obstinate ulceration of the tonsils and pharynx observed in a worker in a bichromate factory. No such extensive ulceration as he describes has been recorded since.

A very complete description of the processes and of the clinical symptoms shown by the persons employed, together with suggestions for improving the conditions of working, was given in a joint paper by Delpech and Hillairet[106] in the years 1869 and 1876. They believed that any part of the skin might become ulcerated if exposed long enough to the action of the dust. In no case did they find that the ulcers penetrated into the joints, or that the bones of the nose were attacked. They believed that the action of the dust set up in some cases bronchitis and asthma.

In 1893 the effect of bichromate on the health of the workers was referred to in the Report of a Departmental Committee of the Home Office on the conditions of labour in chemical works, and, as a result, special rules prescribing protection of vessels containing bichromate in solution, respirators, due means for the removal of dust, waterproof gloves, and lavatory accommodation, were drawn up.[107]

In 1895 the conditions found in the German bichromate factories was made the subject of an interesting official report by Dr Wutzdorff,[108] assisted in the chemical part by Dr Heise. Following upon the recommendations made by Dr Wutzdorff, stringent regulations were drawn up to govern the industry in Germany.

In 1899 considerable stir was created in Glasgow by the publication by the Labour Leader of a series of pamphlets directed to show, among other things, that in certain factories in Scotland the conditions of work were still unhealthy. In that year I visited all the factories in this country, and a code of special rules printed elsewhere in this volume now governs the industry.

Potassium bichromate is made by roasting a mixture of chrome ironstone, potash and lime, lixiviating the fused mass with water, and adding enough sulphuric acid to convert the neutral chromate into bichromate. The reaction may be represented as follows:--

Cr_{2}O_{3} + 3O = 2CrO_{3} CrO_{3} + K_{2}CO_{3} = K_{2}CrO_{4} + CO_{2} 2K_{2}CrO_{4} + H_{2}SO_{4} = K_{2}SO_{4} + K_{2}Cr_{2}O_{7} + H_{2}O.

Sodium bichromate is made in practically the same way, sodium carbonate taking naturally the place of potassium carbonate. In the crushing and grinding of the chrome ironstone much dust permeates the air, but this mineral dust does not give rise to the peculiar lesions associated with the bichromate.

After having been ground to a fine impalpable powder the chrome ironstone, mixed with lime and potash, is introduced into a furnace and roasted for about three hours. When withdrawn from here the fused mass or “batch,” as it is called, consisting of neutral chromate of calcium and potassium, after being allowed to cool, is broken up and shovelled with evolution of much dust into large vats or “keaves.” Water and potassium sulphate in solution are added, and at this stage, owing to the slaking of the uncombined lime, much steam, carrying with it particles of chromate dust, arises. The solution, when concentrated by passing through successive keaves, is pumped into evaporating pans, which are almost invariably entirely covered in and communicate with the outside air by means of a shaft running through the roof. Sulphuric acid is next added, forming potassium sulphate and potassium bichromate. The former is withdrawn, and the latter, when sufficiently concentrated, is pumped into lead-lined tanks, where crystallisation is usually completed within three weeks. The crystals form beautiful large adherent masses on the sides and floor of the tanks. They are broken up by a pick, removed on barrows to be washed, dried in open stoves by hot-air or steam-pipes, and finally packed in barrels.

Sodium bichromate does not usually crystallise, but forms a solid cake which requires to be broken up.

The particular lesions associated with the manufacture are found among all classes of men employed, from the moment the fused mass is removed from the furnace, until the crystals are headed up in the barrels. Inasmuch, however, as all the processes are carried out in one large common shed, it is a little difficult to determine the relative degree of danger attaching to each operation.

The rafters immediately above the keaves are coloured a canary yellow, from the neutral potassium chromate carried up by the steam; a sheet of cardboard suspended at a height of 2 feet above an evaporating pan becomes covered in a short time on its upper surface with innumerable small brown specks of bichromate--a precipitation which must result from the cooling of the steam; a stranger present for only a few minutes while the packing is being done has the mucous membrane of his nose acutely inflamed for hours or even days afterwards. These facts show how permeated the atmosphere in the shed can become from the dust and fumes from the bichromate. Breaking the crystals is the source par excellence for the development of chrome sores.

Dr Heise, in the paper already referred to, estimated quantitatively the amount of bichromate dust in the air where the different processes were carried on. Thus he found 1 cubic metre of air near to the place where three men were breaking up a cake of sodium bichromate contained 6.30 milligrammes. One cubic metre taken during the fifteen minutes during which packing was done contained 1.57 milligrammes. As regards the steam, he found 1 cubic metre taken at a height of 45 centimetres above the level of the evaporating pan contained 0.736 milligrammes of sodium bichromate. In general, considerably less bichromate was found in the air over the evaporating pan than where the dusty processes were carried on.

The following is the result of an examination I made of 176 men exposed to work at one time or another in the chrome house:

+---------+-------+-----------+----------+--------------+-------------+ | | | | |Sense of Smell| Number with | | Number |Septum | Septum | Septum | Lost or | Unhealed | |Examined.|Normal.|Perforated.|Ulcerated.| Impaired. |Chrome Sores.| +---------+-------+-----------+----------+--------------+-------------+ | 176 | 30 | 126 | 20 | 16 | 39 | | 100 | 17.0 | 71.6 | 11.3 | 9.9 | 22.1 | +---------+-------+-----------+----------+--------------+-------------+

In most of the cases where the septum was found ulcerated but not perforated, the duration of employment had not been sufficiently long for the ulceration to proceed to perforation.

In none of the 30 men in whom the septum was found to be normal was the immunity attributable to shortness of employment. Six were connected with the management, 6 were blacksmiths or coopers, 10 were furnacemen, 4 were engaged at the keaves, and 4 in the crystal house. One-half of them had been employed for upwards of ten years.

There can be no doubt that the mucous membrane covering the septum is attacked more readily in some persons than in others, and I incline to the view that an immunity may be acquired if the first few months are passed without ulceration taking place.

The rapidity of its onset is remarkable, as is shown by the following table:--

Duration of Employment where the Ulceration had not progressed to Perforation.

+------------+------------+---------+--------+----------+ | 2 Weeks or | 2 Weeks to | 3 to 12 | 1 to 3 | Over | | less. | 3 Months. | Months. | Years. | 3 Years. | +------------+------------+---------+--------+----------+ | 3 | 7 | 5 | 4 | 1 | +------------+------------+---------+--------+----------+

Perforation was noted as having already occurred in one instance where the duration of employment had been seven weeks, and in two others it had been less than three months. Usually, it appears to take place between the sixth and twelfth month after commencing work. Most of the men examined worked in the crystal house, and all except the four mentioned had either ulceration or perforation of the septum. The majority of the furnacemen also had perforation, but in them the septum was found normal more frequently than was the case with the men employed in the crystal house.

Nature of the Perforation.--The cartilaginous framework of the nose consists of five pieces, the two upper and the two lower lateral cartilages, and the cartilage of the septum. The two upper and the two lower lateral cartilages give the nose much of its shape, and form the alæ nasi. The ulcerative process due to bichromate dust never attacks them. The cartilage of the septum is somewhat triangular in form, and thicker at its margin than at its centre. Its anterior margin, thickest above, is connected from above downwards with the nasal bones, the front part of the two upper lateral cartilages, and the inner portion of the two lower cartilages. Its posterior margin is connected with the perpendicular lamella of the ethmoid; its inferior margin with the vomer and the palate processes of the superior maxillary bones. The seat of election for the ulceration to commence is a point about a quarter of an inch from the lower and anterior margin of the septum, and it extends in a direction upwards and backwards.

The limitation of the perforation to the cartilage of the septum is accounted for by the fact that the mucous membrane covering it is adherent, forming the perichondrium, and is far less vascular than the mucous membrane lining the rest of the nasal fossa. Once the mucous membrane is destroyed, the blood supply to the cartilage is cut off, and necrosis ensues. The ulceration having progressed upwards as far as the junction of the septum with the ethmoid and backwards to the vomer, becomes arrested. Healing then takes place, the bone not being attacked, and the cicatrix usually becomes covered with an ecthymatous crust of mucus.

In no instance was the anterior or lower border of the septum destroyed. Consequently, the rigidity of the parts is maintained, and deformity, so prominent in other ulcerative processes attacking the nose, absent.

The onset of the morbid process is ushered in by sneezing and the ordinary symptoms of nasal catarrh. The pain accompanying the ulceration appears to be insignificant. It had never been severe enough to necessitate absence from work or to call for medical treatment.

Once the perforation is established, the only inconvenience which results is the formation of plugs of mucus in the nasal passages. The general health is in no way detrimentally affected by the condition. Considering the extent of the lesion, the number found with marked impairment of the sense of smell is not large. Mucous deposits and white patches were occasionally noted on the pharynx, but definite ulceration, such as has been described in bichromate workers, was in no case detected. Asthma, noted by the French writers on the subject, Delpech and Hillairet, was found in one instance--that of a partner in one of the works. In his case there was a family predisposition to it, but the first definite attack dated from contact with bichromate.

Ulceration of the Skin.--In 39 out of the 176 men engaged in chrome processes, one or more unhealed ulcers or “chrome holes” were observed. In these and in several others, numerous scars marking the site of bygone ulcers were noted.

A chrome hole is a sluggish ulcer. It results from a cut or abrasion of the skin coming into contact with bichromate in the form of crystals or solution. The seat of election is either on the knuckles or at the base of the nail, but they may occur on any part of the hands or forearm. In two cases they were observed on the neck, once in the groin, and once on the foot. The tissues around are raised, thickened, and indurated; the centre is filled by a slough, usually covered by a scab, and the whole resembles a large boil. When the slough has been removed the floor of the ulcer is seen to consist of greenish-yellow granulation tissue. In the majority of cases the central scab is not more than ⅛ inch in diameter, in a few it is ¼ inch, and the largest that I have seen measured, ¾ by ½ inch. Chrome holes occur principally among men engaged in the crystal house and at the keaves, and only rarely among the furnacemen. The amount of pain and inconvenience they cause is considerable. Sometimes they necessitate absence from work, but they are never a menace to life. At one works six men were absent during 1898 for periods varying from three to nine weeks, on account of chrome holes. Even when their severity is not such as to necessitate absence from work, months may elapse before they heal.

The treatment adopted by the men is of the most elementary description, and naturally under these circumstances they prove intractable.

The conditions found by Dr Wutzdorff in the German bichromate factories were very similar. Ulcers of the external skin were found most frequently on the fingers, hands, and arms, then on the feet and legs; once an ulcer was found in the external auditory meatus and three times on the eyelids. The ulcers penetrated deeply into the soft parts, and required, in consequence, a long time to heal. In no case had they penetrated as far as the tendons, or into the joints. Ulceration and perforation of the septum was found in workers in several factories, and ulceration of the gums and pharynx of slight extent was observed twice. The general condition of the workpeople was apparently good--at all events no worse than that of chemical workers generally.

The preventive measures necessary in the manufacture of potassium or sodium bichromate will be found stated in the regulations printed elsewhere in this volume. They resolve themselves generally into removal of dust and fumes, cleanliness, and medical supervision periodically of the workers, and the covering up of cuts and abrasions with suitable dressings. When in solution the salt does not attack the unbroken skin. Indiarubber gloves are sometimes worn by the men in dye-works who are constantly engaged in processes in which bichromate is used in dilute solution, but in view of the difficulty of enforcing their use, and the fact already stated, that unless there is an abrasion of the skin a chrome hole will not be developed, the wearing of indiarubber gloves, while a thing to be recommended, can hardly be made compulsory. It is advisable that in all dye-works the foreman should be made responsible to report all men suffering from abrasions of the skin, or from chrome holes, to the manager, in order that they may have proper treatment, and be put to other work until such time as healing has taken place.

In photographic processes involving the use of bichromate, if there is any tendency to the development of eruptions on the hands, careful washing and subsequent treatment, when thoroughly dried, with lanolin or glycerine should be tried. If this fails, rubber gloves must be worn.

T. M. LEGGE.

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XXX. COPPER AND BRASS

The two substances, the dangers to health attendant on the working of which form the subject of this chapter, present widely different features, both as regards their essential natures, their treatment during the processes of manufacture, and the treatment they subsequently receive. The one being a metal and the other an alloy, the primary processes in the first case are those of mining and of reducing the ore; while in the second, the admixture of metals in such proportions as the particular alloy requires is the first detail of treatment. A similar process of casting into ingots follows with both substances, but the malleable and ductile qualities of copper render its subsequent treatment, in the various processes of manufacture, dissimilar to that of brass and its kindred alloys.

There are, moreover, marked features of dissimilarity in the constituents of brass and of copper ore of especial importance in any consideration of unhealthy conditions attendant upon working in these substances. The form of copper ore which is most largely smelted in England is copper pyrites, an ore which is largely composed of sulphur, while in various ores arsenic is found. Brass and similar alloys, on the other hand, are composed of copper and zinc; and as we shall see later in this chapter, it is to the presence of the latter ingredient that in our opinion may be attributed the illness known as “brassfounders’ ague,” or at all events the abnormal amount of ill health found to exist amongst brass mixers and casters.

Although it might be more natural to discuss the metal in the first place, and the alloy of which it forms a very important part in the second, we will reverse that order, owing to the much greater degree of importance, from a sanitary point of view, which attaches to the working of brass than to that of copper. Prefacing, therefore, our remarks on the dangers attending the working in brass by an outline of the processes involved, it will be sufficient for our purpose to quote from a Report of a Committee of the Home Office appointed in 1894 to inquire into the conditions of labour in the manufacture of brass and of kindred amalgams, and of which we had the honour of being members. It is explained that, in the first instance, an alloy is made at a very high temperature in crucibles which are plunged into sunken furnaces, the principal components of the alloy being copper and zinc (commonly called spelter) mixed in proportions varying in accordance with the quality of brass required. An example of a deposit resulting from the pouring of common or yellow brass taken by the Committee is as follows:--

Moisture 9.64 Organic matter 39.42 Silicious residue 9.14 Oxide of iron 2.78 Copper 1.71 Oxide of zinc 28.82 Other matter 8.49 ------ 100.00

Other amalgams, such as gun metal, phosphor bronze, and bell metal, yield different proportions, while in some cases it is found that old copper and brass scrap, such as discarded locomotive and marine boiler tubes, are thrown into the mixture. The alloy thus mixed is poured into iron moulds or ingots, to be remelted when required; or it is at once poured into moulds which have been already prepared by patterns to receive the metal, and in which the formation of the castings takes place. Previously to receiving the metal the mould has been dusted over with fine dust either of burnt loam, sand, burnt red brick, charcoal, French chalk, or bean flour, according to the requirements of the work. The moulds are, roughly speaking, iron rims clamped together, and filled with very fine sand in which the patterns have left impressions for the reception of the metal, hence the name of sand-casting possessed by this process. Should the metal be required for sheets, tubes, or wire, it is poured into iron moulds or ingots, to be subsequently rolled or drawn as required, and this process is called sheet or strip casting. Having procured its shape, the brass article or casting is subjected to further processes on its way to completion, such as (1) that of dipping in aqua fortis and in acid solutions of various strengths for the purpose of removing oxidation and impurities; (2) that of burnishing or of polishing at a lathe to acquire a smooth surface; (3) that of finishing or dressing; and finally (4) that of lacquering, which is an application of a solution of shellac and other ingredients to the work (specially heated for its reception on a stove) with a view of securing the colour desired; also (5) a process of bronzing is also undergone when a particular effect is required in the appearance of the article. In either of these processes, which involves the pouring of the molten alloy, the zinc deflagrates during the pouring, and a dense white smoke is formed, which almost instantaneously fills the atmosphere of the casting shop. This smoke is rapidly converted into snow-white flakes and white powder, consisting of the oxide of zinc, which remains for some time diffused through the atmosphere of the shop, and in ill-ventilated casting shops collects upon the rafters and ceiling in the form of a dense white incrustation. The quantity of these fumes depends, firstly, upon the amount of zinc employed; secondly, upon the ventilation of the shop; thirdly, upon the weather--a dull, foggy day preventing their escape. It may be readily imagined that persons exposed to the alternations of heat and cold in the casting shop, to the deflagrated zinc inhaled as well as imbibed with food and drink, and the intense thirst induced by the nature of the work, would suffer in health. That such is the case the evidence submitted to the Home Office Committee was ample and conclusive. It must not, however, be assumed that nothing was previously known upon the subject, or that no steps had been already taken in the endeavour to improve the shops or in other ways to ameliorate the condition of the workers.

The recognition of working in and making brass as causative of disease is due to Dr Headlam Greenhow, who, in 1862, read before the Royal Medical and Chirurgical Society a paper on “Brassfounders’ Ague.” This was based on his experience while paying a brief holiday visit to Birmingham in 1858, in connection with his investigation of trades injurious to health. It is curious that he should have selected for his title the name of a disorder which undoubtedly occurs, but which, as we shall endeavour to show, is only an acute expression of a chronic malady, and one which rarely or never comes within the range or experience of practising physicians. In the out-patient department of the Birmingham hospitals one meets with an enormous number of brass-workers complaining of various pulmonary and gastric disorders; but an experience of many years has never yet produced to us a case of this so-called ague, although questions will very frequently elicit the statement of its occurrence. The literature of the subject is very scanty, but Greenhow quotes Thackrah’s essay on the “Effects of Arts, Trades, and Professions on Health and Longevity,” published about 1830, as well as the writings of a few Frenchmen, which have not, however, materially advanced our knowledge of the disease. Thackrah’s observations were clearly inaccurate and imperfect, for he mentions only “ague,” which he speaks of as an intermittent fever, attacking brass-workers from once a month to once a year, and leaving them in a state of great debility. Dr Hogben, Physician to out-patients at the Queen’s Hospital, Birmingham, published a very interesting paper on this subject in the Birmingham Medical Review in May 1887. Dr Greenhow refers only to ague and bronchial disorders, and very cursorily to nervous troubles, as resulting from brass casting; but Dr Hogben mentions also colic, constipation, and dyspeptic troubles which result from this occupation. Dr Greenhow, on the one hand, refers all the symptoms to intoxication by zinc, while Dr Hogben thinks they should be rather referred to chronic copper poisoning. These two metals are the principal ingredients in the making of brass, as already mentioned.

That Thackrah was in error in speaking of brass ague as an intermittent affection, occurring once a month or once a year, is clearly proved by the following positive observation, which is supported by all brass-workers. Ague never occurs among the regular workers, but always affects those who are new to the work, or who resume work after an absence of even a month or a fortnight. If a man resumes work, that is melting or casting, after even so brief an interval, he is sure to have an attack of ague, but he will have only one attack, and remain free until after his next holiday. There is most certainly no kind of regular intermission, and according to brass-workers themselves, they only suffer till they are inured to the poison. The following are the symptoms of this so-called ague. After working a few hours, a man becomes languid, depressed, and feels very cold. He is very pale and almost in a state of collapse, his face is covered with a cold perspiration, he shivers, his teeth chatter, and he is restless and anxious. His head aches, there is much nausea and complaint of muscular pains. As a rule he goes or is led home, where he drinks freely of milk and goes to bed. The symptoms continue until he has vomited, either as the result of taking an emetic or independently of it. Vomiting is usually followed by sleep or recovery, with more or less of debility and lassitude on waking. Drs Greenhow and Hogben speak of a more or less marked hot stage succeeding the cold, while following the hot stage they mention profuse sweating. The hot stage may be absent, but the sweating, according to these writers, invariably occurs. Our own observations, based on inquiry amongst those who have suffered from this ague, have never elicited a statement of these hot and sweating stages. Even direct questions as to their occurrence have always been met with positive negation, though some have spoken of free perspiration in the stage of collapse. How to reconcile these statements we do not know. The cycle of events as recorded by Greenhow is just that of ordinary ague, from which this disease differs, otherwise than in the suggested sequence, in toto. The inquiries we have made do not support such a sequence, and certainly not a relationship to malarial ague. The symptoms are just such as would be caused by the ingestion of a quantity of irritant metal, sufficiently large to cause vomiting, and its attendant depression. Such, indeed, is our opinion of the causation of the symptoms, and therefore the name “ague” should not be continued, as being wrongly suggestive and misleading. It will be remembered that it is only when fresh to the work that brass-workers suffer from “ague,” but, though they do not suffer from acute metallic poisoning, they do suffer from its chronic effects, and it is extremely probable that, as with arsenic and opium eaters, they may become inured to the use of the metals.

As it is not very common for brass-workers to use tooth brushes, the accumulating tartar is usually found coloured green. Even when an attempt is made to cleanse the teeth, they still show signs of green discoloration. This has been proved to be due to the presence of copper. The white hair of the workmen is often coloured green, and the underclothing is stained green by the perspiration. The gums may be slightly blackened at the edges, but there is nothing distinctive as in the case of the blue line of lead poisoning; nor, indeed, beyond the green colouring of the hair and teeth, do brass-workers present any unequivocal evidence of their calling.

Ague is not a disorder for which brass-workers consult a medical man; they know how to treat it themselves, and also that it is transitory in its effects; but they come to hospitals in large numbers to be treated for bronchitis. As regards this there is nothing special. The men suffer from it in common with all workers in dusty trades, and so far as we can learn from the Secretary of the Brass-workers’ Organisation, they usually die from chronic bronchitis or fibroid phthisis, unless they succumb to some acute malady. The existence of nervous disorders, especially paralysis agitans, has been said to be common among them, but we cannot find that a larger percentage of brass-workers than of the rest of the community suffers from diseases of the nervous system. It is common, however, to meet with complaints of disturbance of the digestive function. Brass-casters suffer from dyspepsia, loss of appetite, gastro-intestinal catarrh, nausea, vomiting, metallic taste, thirst, colic, constipation, and diarrhœa. They are often nervous and hypochondriacal, and complain of headache as well as muscular pains. There is nothing distinctive about any of these disorders, except the obstinacy with which they resist ordinary methods of treatment, and the readiness with which they yield to the administration of iodide of potassium in combination with the other drugs indicated by the various conditions of ill-health. All the symptoms bear a remarkable resemblance to those produced by chronic copper poisoning. In Guy and Ferrier’s Forensic Medicine, an outbreak of copper poisoning from the use of copper vessels in cooking is recorded, in which the symptoms were almost identical with those here mentioned. The inmates of a convent suffered severely from obstinate and severe colic, retching, and bilious vomiting, costiveness, and flatulence, burning pain in the pit of the stomach and extremities, and paralytic weakness in the arm. According to Stephenson it is impossible to distinguish between the symptoms produced by zinc and copper poisoning. These are just such as brass-workers suffer from, and it is, therefore, impossible to say which metal--copper or zinc--is most concerned in the production of these symptoms. Dr Greenhow attributes them all to the inhalation of the deflagrating zinc. This forms oxide of zinc, which is only sparingly if at all soluble, and, therefore, is not likely to be freely absorbed into the stomach. Greenhow pays little or no attention to the common and chronic gastric and intestinal troubles to which brass-workers are liable. These affect all who work in the various processes by which, either in vapour or in minute particles, copper and zinc--that is, brass--are distributed in the atmosphere. Dr Hogben, on the other hand, considers copper alone to be the efficient cause of the symptoms, and advances the following arguments:--

1. We have no evidence that the internal administration of zinc ever produces the symptoms of brass ague. Enormous doses of the oxide have been administered without apparently producing the characteristic febrile reaction of brass ague.

2. The malady is observed in individuals whose work is other than casting.

3. The malady is not observed in operatives, such as galvanised iron workers, who work with zinc, and are exposed to its fumes.

4. Zinc is rapidly excreted, and does not, like lead, mercury, or copper, become fixed in the body, and produce chronic affections.

It seems more probable that, accepting Stephenson’s statement of the impossibility of distinguishing between the effects of acute copper or zinc poisoning, the symptoms of ague are due to an admixture of the two metals; whereas, for the chronic complaints, the copper is responsible. How the practice of taking milk during an attack of so-called ague has arisen is not clear; but its wisdom is proved by the fact that in cases of both copper and zinc poisoning milk is one of the best antidotes, since it precipitates both these metals into insoluble albuminates. It is abundantly evident that brass-workers are especially liable to diseases from the use of the metals employed in its manufacture, but these are not new disorders; they are either proofs of chronic poisoning by zinc or copper, or, as in the so-called ague, are due to intoxication by them. If more proof were wanting of the unhealthiness of brass-casters, it would be afforded by the fact that a few years ago, though there were 1200 casters in Birmingham, there were not more than ten over sixty years of age, and in connection with a superannuation fund of the Amalgamated Brass-workers’ Association from which casters could at the age of fifty-five derive benefit, it is an appalling fact that there were only three men--two in Birmingham and one in Sheffield--enjoying this benefit.

That such a condition of affairs should be allowed to remain unremedied, if remedy was possible, was improbable after special power was vested in the Home Secretary by the Factory Act of 1891 to deal with processes which he deemed dangerous or even injurious to health.

The desirability of observance of certain general principles, such as temperance, cleanliness, and care in the matter of taking food, was obvious not less in the case of brass-workers than of other operatives. These need not be enlarged upon by us, although their importance towards securing health and happiness in a man’s declining years are sadly overlooked among the working classes. But it was felt that there should be some definite rules officially published for the healthy conduct of brass-working.

A series of rules designed to that end were tentatively issued with the approval of the Secretary of State by Mr R. E. Sprague Oram, C.B., then Chief Inspector of Factories in 1894, but although possessing features of stringency which appear not unwarrantable under certain conditions of brass-working, they were generally felt to be unnecessary in the case of working in alloys in which the percentage of zinc was either relatively small, or indeed from which it was entirely absent.

Official attention had, however, been thoroughly aroused to the necessity of action, and in November 1894 a Departmental Committee was appointed by Mr Asquith, Secretary of State, to report upon conditions of work, so far as they affected the health of operatives in the various processes connected with the working of brass, gun metal, bell metal, and other kindred amalgams. Subsequently too at Birmingham, which may be regarded as the home of the brass trade, the Committee held sittings and made inquiries in various parts of London, in Willenhall, Wolverhampton, Edinburgh, Glasgow, Sheffield, and Rotherham, and were assisted by the evidence of a large number of manufacturers, artisans, factory inspectors, physicians, and others, on which their report to the Home Secretary of State was based. The report largely deals with matter already given in this chapter, but drawn as it was immediately after the accumulation of the best evidence on the subject which could be procured, and for the elicitation of which no further opportunity is likely to arise for the present, it is desirable that the conclusions arrived at should be given. Having stated that during the inquiry the Committee had met with ample evidence of the existence of such symptoms as have been described above, the report adds that the attention of the Committee had been, by personal observation and experience, especially drawn to the causes and symptoms of the so-called “ague,” of which the members had no reason to doubt zinc fumes were the efficient cause; that it considered the danger of working in the several alloys was proportionate to the amount of zinc contained; that the danger was increased by the use of such ingredients as discarded locomotive and boiler tubes, and such-like scrap; also that the symptoms were caused by the inhalation of the zinc fumes, and by the introduction of the particles of zinc into the digestive tract with such food as might be eaten in the casting shop. The conclusion arrived at was that, “Although in brass-casting, as in all other occupations, the practice of personal cleanliness may serve to reduce the ill effects incident to the workers’ employment, yet if a brass-caster is constantly exposed to the influence of these fumes, it remains almost an impossibility that he should pass unscathed by them. The most serious efforts, therefore, should be directed by manufacturers and artisans alike towards the minimising of the ill effects which must of necessity be caused in the process of casting by these fumes; and the Committee are convinced, both from personal experience and from evidence which they have acquired from witnesses of all classes, that the direction of these efforts should lie towards securing a proper construction of casting shops, supplemented by a system of ventilation conducted on scientific principles.”

Shops properly constructed, scientifically ventilated, adequately provided with washing arrangements for the casters, and licensed by a competent authority, were the requirements suggested by the Committee as being absolutely necessary for the casters. The compulsory wearing of mouth coverings during the process of pouring the metal was felt, owing to hostile evidence given by the workers themselves, to be impossible for recommendation. Finding that “a great many witnesses considered milk to be a desirable thing to take when ill, but as a rule they preferred to take it at night, finding that it did not agree with them so well when taken in the shop, and in many cases witnesses did not think milk suited them personally,” the Committee did not consider it desirable to recommend the retention of the tentative rule requiring manufacturers to provide a supply of milk or other sanitary drink. The drinking of milk, however, as well as the wearing of a covering to the mouth and nostrils, was recommended for the casters. Further recommendations were, leaving the shop for the purpose of taking food, frequent ablution, care in the avoidance of taking cold, and of a regular and moderate diet.

Apart from the recommendations for optional courses of conduct were suggestions for specific rules. It was a matter of sincere regret to the Committee to learn that these were in some instances--such, for example, as the desired requirement that casting shops should be licensed--beyond the powers of enforcement vested in the Secretary of State. The special rules which were issued subsequently to the report of the Committee underwent a slight modification more recently, and are now as follows:--

Form 271.

FACTORY AND WORKSHOP ACTS, 1878 TO 1895.

MIXING AND CASTING OF BRASS AND OF CERTAIN OTHER ALLOYS.

SPECIAL RULES.

Under Section 8 of the Factory and Workshop Act, 1891, and Section 28 of the Factory and Workshop Act, 1895, for the processes in the mixing and casting of Brass, Gun Metal, Bell Metal, White Metal, Delta Metal, Phosphor Bronze, and Manilla Mixture.

DUTIES OF OCCUPIERS.

1. They shall provide adequate means for facilitating, as far as possible, the emission or escape from the shop of any noxious fumes or dust arising from the above-named processes. Such means shall include the provision of traps or of louvre gratings in the roof or ceiling of any shop in which such processes, or either of them, is or are carried on; or in case of a mixing or casting shop which is situated under any other shop, there shall be provided an adequate flue or shaft (other than any flue or shaft in connection with a furnace or fireplace) to carry any fumes from the mixing or casting shop, by or through any such shop that may be situated above it.

2. They shall cause all such mixing or casting shops, whether defined as Factories or as Workshops under the Factory and Workshop Act, 1878, to be cleaned down and limewashed once at least within every twelve months, or once within every six months if so required, by notice in writing from H.M. Inspector of Factories and Workshops, dating from the time when these were last thus cleaned down and limewashed; and they shall record the dates of such cleaning down and lime-washing in a prescribed form of register.

3. They shall provide a sufficient supply of metal basins, water, and soap, for the use of all persons employed in such mixing or casting shops.

4. They shall not employ, or allow within their Factory or Workshop the employment of, any Woman or Female Young Person, in any process whatever, in any such mixing or casting shop, or in any portion thereof which is not entirely separated by a partition extending from the floor to the ceiling.

DUTIES OF PERSONS EMPLOYED.

5. They shall not partake of, or cook any food in any such mixing or casting shop, within a period of at least Ten Minutes after the completion of the last pouring of metal in that shop.

B. A. WHITELEGGE, July 10, 1896. H.M. Chief Inspector of Factories.

(Note.)--WOMEN and PERSONS under 18 YEARS OF AGE are by the 39th section of the Factory and Workshop Act, 1878, expressly FORBIDDEN either to TAKE A MEAL or to REMAIN in any casting shop during the time stated on the Notice affixed in the factory or workshop as being allowed for meals; and the obligation of enforcing this section rests with the occupier.

* * * * *

These Rules are required to be posted up in conspicuous places in the Factory or Workshop to which they apply, where they may be conveniently read by the persons employed. Any person who wilfully injures or defaces them is liable to a penalty not exceeding five pounds (Factory and Workshop Act, 1891, section 11). Occupiers of factories and workshop, and persons employed therein, who are bound to observe any special rules, are liable to penalties for non-compliance with the same (Factory and Workshop Act, 1891, sections 9 and 11).

These rules will be found to strike at the three principal causes of illness in the workers, viz.: (1) shops either structurally unfit for the processes of mixing or casting metal, or equally unfit on account of their dirty and zinc-coated condition; (2) the want of opportunity afforded to the casters of washing themselves before taking meals; and (3) the most pernicious habit, too common hitherto with the workers, of taking food in an atmosphere of deflagrated zinc. It will be noticed also that a prohibition is laid upon the employment of females in casting-shops. Their labour in connection with such work is limited to the making of cores, small blocks of sand which are used in the formation of hollow castings. The evidence of the witnesses examined before the Committee was in favour of this prohibition, also of core-making being carried on in a separate shop.

With regard to the other processes met with in brass-working, and which have been enumerated in an earlier part of this chapter, it cannot be said that they present any causes of illness differing from like processes in connection with other metals. Workers in the dipping-shop, and to a less extent in the bronzing process, are exposed to inhalation of acid fumes, and further, in the former occupation to exposure to the weather and to being obliged to stand on very wet floors. In a case brought to our notice, the powder used in bronzing contained lead to an extent of 7 per cent., a condition which might induce plumbism in the worker in the absence of due precaution. The dust which is given off during polishing is partly metallic in character, partly composed of a mixture of sand and lime, and partly textile fluff worn off the calico polishing discs by the process of work. Without doubt such dust should, as in all factories, be removed by fans or other ventilating methods from the shop. The shops used for lacquering should similarly be freed from the unpleasant fumes of the lacquer, which cannot, however, be considered in any particular degree injurious to health. A most interesting paper read before the Midland Medical Society by Dr William Murray (subsequently printed in the British Medical Journal, 2nd June 1900) on Chronic Brass Poisoning, draws attention to another rather common form of plumbism caused by the process of “putting together” gas fittings, it being customary to solder the joints of these fittings with white lead, and then having closed one end of the bracket, to suck at the other to ascertain that the work is perfectly sound. We have recently met with a case of advanced paralysis in a man of forty-five apparently induced by this branch of brass-work. Dr Murray deals in detail with his method of treatment of cases of chronic brass poisoning, of which as Resident Surgeon of the Birmingham General Dispensary he has had considerable experience.

We hope we have shown that, firstly, the conditions of brass-working in all its branches require that the shops in which it is carried on should be well ventilated in order to secure the escape of the “smother” from the casting-shops, and of the conglomerated dusts from the polishing rooms; and secondly, these conditions require or rather demand habits of personal cleanliness and of self-respect on the part of the workers, habits which prescribe temperance, avoidance of taking food in the shop, and frequency and regularity of ablution. Such are now possible of attainment by the persons whose health is concerned, and it rests with themselves alone to make full use of the improvements placed within their reach.

Passing from the consideration of brass to that of copper, we find that there is little to be said regarding the working of that metal descriptive of any injury to health among its workers. Indeed it may be doubted whether any traces of such injury can be found. Having been mined in many quarters of the globe, the ore is subjected to the process of smelting, which, so far as Great Britain is concerned, takes place chiefly at Swansea, and also at St Helens and at Newcastle-on-Tyne. The qualities of the ores from different mining districts vary greatly, and the reducing processes of the ores vary correspondingly. Speaking generally, it may be said that the process consists of six operations conducted in reverbatory furnaces, termed calcining and melting furnaces. At the conclusion of these processes the metal, freed from the arsenic, sulphur, and other accessories of the ore, is melted and cast into ingots, to be sent in that shape to various centres for manufacturing purposes.

During the smelting processes the sulphurous fumes either are collected in leaden chambers for purposes of condensation into sulphuric acid, or escape through the flues into the outside air. In neither case does the worker at the furnace suffer from these fumes, except, perhaps, when drawing the furnace he may experience some back draft of sulphur, an evil which may readily be met by the wearing of a handkerchief over the mouth while engaged in the operation. During recent years it may be mentioned that the first of the reducing processes is more commonly carried on in the vicinity of the mines, and as a consequence the ore on reaching S. Wales is now usually in the form of regulus. The denuded state of the country in the neighbourhood of the smelting furnaces bears witness to the unhealthy character of sulphur fumes. Dr Arlidge, however, notes an analysis of sickness in the Swansea district which tends to prove that though the fumes were very productive of acute pulmonary disease, yet the death-rate in parts of the country subject to their influence was lower than that in adjacent districts. We are told by Mr Lewis, who for many years has been the Factory Inspector in charge of the Swansea district, that although there is a prevalent impression that the furnacemen suffer exceptionally from chest mischief owing to the great heat and the fumes, he does not consider that they suffer in any degree more than the furnacemen in other metal processes. He forms the same opinion as that held by us in respect of the brass-workers, namely, that the workers are not sufficiently careful of themselves between shifts. He reports that the flue and chamber cleaners, as at other smelting works, rarely wear respirators; they will not ventilate the flues nor water the dust before commencing cleaning operations, and consequently the respiratory organs are more or less affected; he cannot find direct evidence of specific illness traceable to copper smelting. Mr Lewis attaches considerable importance to the provision of high and well-constructed stacks and flues, and to the due preparation of the chambers by ventilation and watering before the process of their cleaning takes place. No special inquiry having been ordered concerning this subject, particular importance attaches to Mr Lewis’ opinion.

On the whole we do not consider that copper-working is in any way as dangerous an occupation as brass-working, for the pouring of metal is not accompanied by the same abundant vapours as in brass pouring, besides such vapour as does arise is mainly due to the presence of a small quantity of spelter in the mixture. The same precautions as advised for brass pourers should be taken, but the need is less; we have seen a pouring shop with a perfectly clear atmosphere five minutes after the pouring has taken place. A muffler or respirator should be worn during the operation, and, as far as we have seen, this is generally done. Apart from the pouring we have been struck by the excellent health of copper-workers, and as the dust is heavy, and does not float in the air, there are none of those respiratory troubles which, as we have seen, are the bane of brass-workers. There is one danger to which apparently they might be subjected, but we found no evidence of its having arisen, and that is from the accumulation of the heavy copper dust on the tables or boards at which the men are working. It seemed not unreasonable to expect that want of cleanliness on the part of the workers would entail digestive troubles from the mixing of copper dust with the food. As we have stated, no evidence of this is forthcoming. It will be seen that we are unable to confirm Dr Arlidge’s view of the dangers to copper-workers from the inhalation of copper dust, nor are we able, though contrary to our expectations, to assert that men employed in the trade are particularly liable to suffer from colic. According to Blaudet, this colic is attended by complete prostration, by vomiting and purging, and it is very probable that such results would follow, if the men were dirty in their work and habits, the introduction of copper dust by food taken into the stomach. Opinions are much divided on this subject, and it is possible that working in old copper and brass, which are covered with a carbonate of copper, may be responsible for the ill effects noticed. According to M. Perron of Besançon, clockmakers, who have to handle copper freely, suffer from a slow intoxication from it, exhibited by gastric derangements, diarrhœa, oppression, and some feverishness, but our own experience among copper-workers and other persons does not confirm these observations.

The conditions of improvement suggested both for brass and copper working are those that should be applied to all manufacturing processes. Shops of good construction, well ventilated, and amply furnished with lavatory and other sanitary arrangements; these are desiderata for the workmen.

ROBERT M. SIMON. SEYMOUR H. KNYVETT.

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