Illustrations of pulmonary consumption; its anatomical characters, causes, symptoms and treatment. To which are added, some remarks on the climate of the United States, the West Indies, &c

Front matter

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Preface

The author of a new book may sometimes be compared to the voyager, who, after circumnavigating the globe, and viewing its mountains, islands, bays, and rivers, returns home without having added much that is new to the chart he took with him : and yet, to continue the metaphor, we may, even under such circumstances, read the narrative with pleasure and instruction ; for, while it revives and confirms our previous knowledge, it perhaps throws some new light on remote and interesting objects.

It may be urged, that the subject of the following memoir has already occupied the ingenuity of so many able writers, as scarcely to leave room for a new idea : but a disease that has ever caused a large proportion of the mortality in almost all countries, and which attacks the human frame in every phasis of its development, from embryo existence to extreme old age, justly claims the untiring scrutiny of the physician.

It has often surprised me, that of the works of Bayle and Louis, we have no American editions. Dr. Forbes's translation of Laennec. is executed with ad-

Vlll PREFACE.

mirable precision and elegance; and had it been republished in this country at the time the present volume was commenced, it is probable the latter would never have been offered to the public.

It may reasonably be asked, what my opportunities have been for an inquiry of so much interest and difficulty, as that which forms the subject of this volume.

My attention was first particularly directed to the diseases of the lungs, by an attendance on the clinical lectures of the celebrated Laennec ; who, with astonishing acuteness of mind, and personal urbanity, combined the faculty of imparting a portion of his enthusiasm to all who heard him.

On my return to this, my native city, I resolved to pursue with ardour an inquiry for which I had imbibed so strong an interest. But facilities are not always at our command ; and before I was able to realise them, several years had already elapsed. At length, in 1829, I received the appointment of physician to the Philadelphia Almshouse Hospital.

The wards of this institution habitually contain several hundred patients; exhibiting almost all the maladies to which man is subject, and especially those of a chronic nature, among which phthisis may be said to predominate. The deaths from this disease alone are little short of one hundred annually; and the fa-

PREFACE. IX

cilities of pathological investigation in this institution are unrivalled on the American continent.

To these advantages I have added others, derived from an extensive private practice; and have long made it a rule to preserve the histories of my cases, and to avail myself of every opportunity of comparing the opinion I had formed during the life of the patient, with the appearances of the body after death.

From a large number of cases thus recorded, I have selected, for this work, such as best serve to give an idea of the various conditions of consumption ; and in many instances the cases are further illustrated by coloured plates.

On these lithographed illustrations I have bestowed the utmost attention ; the preparations from which they were derived, were placed, as soon as obtained, in the hands of an excellent artist, and every character, whether of organization or of colour, was immediately transferred to paper under my personal supervision.

In arranging the cases, many of which have chiefly an anatomical interest, I have, as a general rule, endeavoured to restrict the details to the points under consideration at the time, and to reserve whatever relates to the treatment of phthisis, for the last chapter ; for it is obvious that unabridged histories of this kind would involve interminable repetitions, and extend the limits of this work far beyond the author's design.

PREFACE.

In fact, my original plan embraced little beyond the pathological anatomy of the lungs : but year after year the subject expanded before me, until I have been induced to examine it in nearty all its bearings.

Thus, after the manner of Laennec and Louis, I have commenced with an examination of the anatomical characters of consumption, and have endeavoured to trace its changes from the incipient granule to open abscess. Some brief remarks have been devoted to its pathology, followed by a more extended view of its causes, symptoms and treatment.

Perhaps I should apologise for introducing the initiatory chapter on the morbid changes of structure which accompany phthisis, especially as the remarks under this head are wholly elementary. But it occurred to me that even a brief notice of those changes, might be acceptable to many whose avenues to pathological information have been limited ; and especially as the chapter in question embraces some leading features in morbid anatomy, and principles of general application.

I much regret that, with respect to the relative advantages of climate in different parts of this country, the details should be so meagre, but notwithstanding my sedulous inquiries for facts of this kind, I have met with comparatively little success, although I am

PREFACE. XI

sensible that many sources of information may have escaped my research.

A subject, however, of such paramount interest, cannot remain much longer uninvestigated : and I seize the present occasion to express a hope, that the practitioners in various sections of the United States will give more attention to medical statistics, embracing especially the mean range of the thermometer, the prevalent diseases, comparative tables of mortaility, the changes incident to the progress of cultivation and civilisation, and an examination of the question, how far, in these varied localities, phthisis and scrofula appear to be conjoined.

Medical men attached to the army have great facilities for inquiries of this kind, and those who reside in the vicinity of the Indian tribes, have it in their power to communicate much valuable information. Dr. Hush, in his Medical Inquiries and Observations, speaks of consumption as a disease almost unknown among the aborigines of this continent: while the late Professor Barton maintained the contrary opinion: derived, however, as I have reason to believe, from the prevalence of scrofula among some of the more northern tribes.

Few inquiries are more interesting to medical men, than those which illustrate the influence of the refinements of civilised life in the production of disease ;

Xll PREFACE.

and in no instance can this question be examined with more interest than in reference to consumption.

As the result of several years observation and reflection, I now submit this work to my professional brethren; and if in its pages they meet with fewer novelties than they could have desired, I trust they will at least award me the merit of illustrating an intricate subject in a conspicuous manner; for it has not been my object to originate a striking hypothesis, or to advance imposing novelty in practice : but rather to convey, with reasonable brevity, the results of my own observation and experience, compared with the views of those who have preceded me in this inquiry.

I cannot conclude this preface without expressing my grateful thanks to those resident physicians of the Philadelphia Alms-house Hospital, whose aid will be more specifically acknowledged in the course of the following pages; and whose professional zeal and intelligence have been of infinite service to me in the pursuit of my inquiries.

Finally, whatever acknowledgments an author can owe to his publishers, I owe to mine ; more especially for their unhesitating liberality in meeting the heavy expenses inseparable from a work of this kind.

Philadelphia, December 1, 1833.

Preface To The Second Edition

Three years have now elapsed since the first publication of this work ; and during that interval I have availed myself of every source of information on the subjects of which it treats. The former edition is, therefore, but the skeleton of the present one : for it will be observed that the whole work has been rewritten, and that the quantity of matter (exclusive of the numbered cases, which remain nearly as before) is considerably more than double.

Within the period above mentioned I have also enjoyed the advantage of personal observation on the climate of some of the West India islands. The result of my inquiries on this head are recorded in the following pages, and will be found, I trust, to embrace some useful information.

Since this work first appeared, several authors of celebrity have published the result of their observations on the same subject : among them I may especially mention Drs. Clarke, Davis, and Latham. The work of M. Louis has been translated into English, and ably edited by Dr. Cowan : and I have also read, with

XIV PREFACE TO THE SECOND EDITION.

great instruction, some recent memoirs in the French Journals. Of these last, however, the value is mainly statistical ; and in order to subserve the purpose of comparison, I have given, in the Appendix, such abstracts as appeared most deserving of attention.

S. G. M.

431 Jlrch Street, Philadelphia, February 8, 1837.

Contents

Page Chap. I. Brief view of those Morbid Conditions of the lungs and

their appendages, which usually co-exist with Phthisis, 17

II. Anatomy of Tubercular Matter, ..... 30

Chapter I

A BRIEF VIEW OF THOSE MORBID CONDITIONS OF THE LUNGS AND THEIR APPENDAGES, WHICH USUALLY COEXIST WITH PHTHISIS.

In examining the lungs of persons who have died of Phthisis, we almost invariably find the tubercular affection complicated with organic lesions of a different character. It would be foreign to the plan of the present work to enter into the details of these numerous diseases; the following remarks are consequently of an elementary nature designed chiefly to enable the observer to distinguish tubercular matter from the morbid changes that accompany it. Most of these changes may be either causes or consequences of phthisis; although the nicest examinations do not always enable us to say which has been the primary, or which the consecutive affection.

PLEURISY.

Pleuritis. Inflammation of the pleura. — Acute Pleurisy is ushered in by severe, pungent, fixed pain, which is 3 aggravated by every motion of the body, but especially by coughing and speaking, and by efforts at full respiration. The patient is most at ease when lying on the sound side. The pain spreads rapidly from the point of origin, often extending over the whole side of the chest, and even to the opposite side; in the latter case the disease is called a double pleurisy.

If these symptoms are not relieved, the disposition to cough increases in common with an aggravation of pain, dyspnoea, &c. The countenance assumes an expression of great anxiety, is of a livid colour, and a sense of suffocation continues almost to the moment of death.

Pleurisy commonly produces one or more of the following morbid changes in the pleura: these changes, however, do not necessarily involve the life of the patient; for every day's experience goes to show that they are often followed by restoration to health.

Adhesions. — One of the first consequences of inflammation of the pleura, is an exudation, on its external surface, of coagulable lymph, which is in fact the fibrinous* portion of the blood. This is considered by Laennec as a kind of suppuration proper to serous membranes.t It of a yellow, opaque exudation, at first not thicker than cream, but soon acquiring a firmer consistence. This appearance, which is the first stage of false membranes, is often in patches, or rounded granules on the pleura, other portions of the membrane presenting a spotted redness.

* Chemical analysis has proved it to be pure fibrine: M. Andral suggests with great probability, that this principle constitutes the basis of all organised morbid productions, both in parenchymatous and membranous tissues.

t L'Auscult. Med. t. i. p. 331.

The exudation soon becomes organised, firm, and almost inseparably attached, presenting most frequently the following characters:

Thread-like cords, and flattened bands, passing from one surface of the pleura to the other, diaphanous, and sometimes more than two inches in length. Their characters closely resemble those of cellular tissue.

Occasionally these cords attain a great thickness, and in some rare instances enclose adipose matter. (PI. XI. fig. 2.) (Case 18.)

Again, it is not unusual to find the entire surfaces of the pleura closely and directly adherent, by means of numerous layers of cellular tissue resembling the pleura itself. This structure is admirably seen when it coexists with general dropsy.

Finally, there is a species of false membranes of a fibro-cartilaginous consistence, which results from long continued irritation of the pleura. It is formed by successive deposits of lymph between the natural membranes, separating the latter widely apart, and even attaining the thickness of an inch. Its colour assumes various shades of yellow and white, with a tinge of gray. (PI. XI. fig. 1. and PI. IX.) This substance also assumes a spheroidal form, and may be readily mistaken for tubercles.

When the secretion of lymph takes place in the fissures between the lobes, it may occupy the whole length and breadth of those fissures, and attain a considerable thickness. These white laminated masses may occasion some confusion in an incautious dissection from their resemblance to cicatrices, with which they have doubtless been sometimes confounded.

It sometimes occurs that the secretion of coagulable lymph is accompanied with an effusion of red blood; this constitutes the hcemorrhagic pleurisy of Laennec. (Case 14.)

Effusion. — Effusion into the cavity of the pleura does not necessarily follow the inflammation of that membrane, for it is often absent: but there is sufficient evidence that when it does occur it is mostly simultaneous with the inflammation itself, as Laennec has demonstrated. This fluid is sometimes in great quantity, compressing the lung and suspending its functions. (Case 26.) It is serous, or sero-purulent, sometimes tinged with blood; it is also seen of a light wine-colour, and again of a milky or turbid hue, derived from the morbid secretions of the pleura, which are occasionally observed in flocculent masses swimming in the fluid.

When, in consequence of a wound of the pleura, blood is effused into its sac, the disease is called Hemothorax.

That kind of effusion which is occasioned by ulcerous perforation of the pleura, will be more particularly noticed hereafter.

PNEUMONIA.

Peripneumonia. Pneumonitis. Inflammation of the lungs. — Inflammation of the lungs generally commences with a chill, and pain in some part of the thorax, followed by oppression, difficult respiration, cough and expectoration of a viscid mucus, more or less mixed with blood. The skin becomes hot, the face flushed, the pulse full and frequent, the breathing laborious and hurried, and the anxiety extreme.

PNEUMONIA. 21

According to the duration of pneumonia, it induces one or several of the following pathological conditions:

1. Engorgement. Engouement. — Inflammation of the lungs is probably confined, at least in its incipient state, to the cellular tissue* of those organs, which is then engorged with blood, rendering them more dense than natural, and of a livid colour with a violet tin^e. The sero-sanguineous fluid shows freely from an incision. If in this state the lungs be carefully washed, they resume their crepitancy and other natural characters.

This stage is susceptible of perfect resolution.

2. Red hepatization. Ramol/isscment rouge. (Andral.) Carnification. — This condition marks the second stage of pneumonia. It is readily identified by its deep red colour, its firm consistence, and its solid appearance; the lung no longer floats in water, and, if torn, presents a rough, granulated surface, like that of the liver. (PI. III. fig. 2.) When cut into, scarcely any moisture escapes; but if pressure be applied near an incised surface, a small quantity of sero-sanguineous fluid flows out. An incision also exposes numerous white points and lines, which are unaltered portions of the blood-vessels and bronchial canals. I have known these points to be mistaken for tubercles.

This stage is also susceptible of entire resolution.

3. Yellow hepatization. Purulent infiltration. Ramollissemcnt gris. (Andral.) Suppuration. — This is the third stage of pulmonary inflammation, and presents the following characters:

o

•There is a difference of opinion on this head among pathologists, some of whom suppose the air-cells to be the seat of disease.

The lung is hard and granulated, as in the former stage, and has a remarkable straw-yellow colour, mostly pale, but occasionally in young persons of a brighter hue. If the lung be cut, an opaque, viscid, yellowish fluid escapes, resembling pus. The yellow portions of lung are often interspersed with patches of red hepatization, giving the incised surface a marbled appearance, not unlike certain adipose conditions of the liver.

Resolution sometimes follows this stage of pneumonia.

4. Induration. Induration grise et rouge. (Andral.) — If, after hepatization has taken place, resolution does not follow, the lung gradually loses its red colour, and assumes a light gray tint. In some instances, however, it retains a dull red hue. This morbid structure is of a dense, dry consistence, often with a reticulated appearance from some remains of the air-cells, and mostly interspersed with tuberculoid granulations. When incised it yields a sound not unlike that obtained by cutting a sponge. Tubercles frequently form in it. (PI. IX.)

I cannot believe with some authors, that gray induration ever results from simple chronic inflammation; but that, on the contrary, it is always preceded by acute inflammation, which not being resolved in its third stage, leaves the lung dense as in hepatization; the red globules and much of the granular structure having disappeared.

5. Abscess. — This is an extremely rare termination of simple pneumonia; so much so, that Laennec says he met with it but five or six times in many years.* The parietes of the cavity are formed by the surrounding pulmonary

* Laennec, L'ausc. Med. — Boisseau, Nosog. Organ. Tom. 2. p. 421.

PLEUROPNEUMONIA. CONGESTION OP THE LUNGS. 23

tissue, and the cavities themselves are generally very small. In a great number of dissections 1 have but twice met with this condition of the lung. (Cases 32 and 33.)

6. Gangrene. — The colour of a gangrenous lung is a dirty green with spots of brown, black, and livid red. Sometimes it is circumscribed, the slough being contained within a distinct cavity, and the adjacent lung preserving a nearly healthy aspect; and at other times the gangrenous characters are gradually lost in the surrounding pulmonary tissue. This disease is mostly accompanied by a peculiarly foetid breath; and the odour of the lung itself is offensive beyond endurance. (Case 32.)

PLEURO-PNEUMONIA.

It is scarcely necessary to observe, that inflammation of the parenchyma of the lungs and of the pleura, frequently occur simultaneously — a complication which embraces the morbid changes proper both to pleurisy and pneumonia.

CONGESTION OF THE LUNGS.

Pulmonary Apoplexy* This is a very frequent disease, but unfortunately is seldom recognised except by one of its principal consequences — Haemoptysis. Congestion, however, is to be suspected, when a person who has enjoyed previous good health, feels a sensation of heat in some part of the lungs, accompanied by oppressed breathing, languor, and alternate coldness and flushing of the

•The name of this morbid condition is due to Rush, (Med. Inq. and Obs. vol. 2. p. 87.) We owe the knowledge of its pathology to Laennec.

face, more especially if these symptoms occur suddenly, and rather simultaneously, and are unconnected with pain. I consider the latter to be the principal yet by no means a certain diagnostic, between this disease and acute pneumonia. The former is not necessarily connected with inflammation, but is often a mere congestion of blood in the inter-vesicular cellular membrane: when the blood permeates the membranes of the air-cells and minute bronchia, haemorrhage is a necessary consequence, and is the only unequivocal symptom of this disease. Its anatomical characters have been elaborately investigated by Laennec, who admits their close analogy to hepatization, and even to engorgement of the lungs, yet draws the following distinctions between them: the apoplectic condition is circumscribed, very dense, brown, or dark red and granulated; when incised, it is dry, and loses its color, but not its firmness, by washing.

BRONCHITIS.

Pulmonary Catarrh* — This disease, so familiar to us by the names of cold and catarrh, is an inflammation of the mucous membrane lining the air-tubes of the lungs. It is at once recognised by its red colour, in some instances extremely bright, in others dull and mottled. The mucous membrane of the nose is often first attacked, the inflammation consecutively involving the larynx, trachea and bronchia. When it passes to the chronic state, ulceration follows, which may be recognised by numerous small,

* This affection is called Peripneumonia notha by the older authors, and is the catarrhus suffocans of Lieutaud.

OEDEMA. 25

irregular, white spots; these, when examined, are found to be partial excavations in the mucous surface. (PI. XII. fig. 2.) When this inflammation becomes chronic in the larynx and trachea, ulceration is sometimes deep and extensive, even destroying the cartilages, and causing those alterations in the voice so common in phthisis. (PI. X.) The long continuance of catarrhal affections, especially that form of them called chronic mucous catarrh, sometimes occasions dilatation of the bronchia. In this pathological state, the air-tubes become preternaturally enlarged, their mucous membrane thickened, and of a violet hue. (Case 15.)

The mucous membrane of the bronchia is capable of secreting genuine pus;* and it will be hereafter shown that there is a form of bronchitis so resembling tubercular disease of the lung, as readily to be mistaken for it.

When bronchitis has been long in a chronic state, and even where all the symptoms of the disease remain active, the bronchial mucous membrane is occasionally seen perfectly pale and colourless throughout. {Case 12.)

(EDEMA.

Hydrops pulmonum. Dropsy of the lungs. — This is an effusion of serum into the interstitial cellular tissue of the lungs: the latter, when examined after death, may be pitted with pressure like the surface of the body in anasarca; they are much heavier than natural; and on being cut and

• "In this disease (Bronchitis) the whole of the Bronchial system seems to acquire the power of secreting matter." Badham on Bronchitis p. 157. The original discovery of this fact in pathology, is variously attributed to Morgagni, De Hatn and Dr. W, Hunter. 4 compressed, discharge a frothy, yellowish serum, after which they become again crepitant.

Although the air-cells are unimpaired, an cedematous lung generally contains very little blood. The disease is mostly symptomatic of other affections, and is often conjoined with Phthisis.

EMPHYSEMA.

Emphysema pulmonum. Pulmonary emphysema. — This is for the most part, constituted by a distension of the air-cells in chronic catarrh, &c. The vesicles not unfrequently observed on the surface of the lung beneath the pleura, are caused by the escape of air from the cells within; the difficulty, however, of pressing the air back into the bronchia, led Dr. Bailey erroneously to suggest that it was secreted by the minute blood-vessels.* When an emphysematous lung is exposed on opening the chest, it does not collapse, but appears rather to expand beyond its natural dimensions.

When the disease is confined to the air-cells, as usually happens, it is called Vesicular Emphysema; but when it pervates the cellular tissue, separating the lobules, it is called Interlobular.

PNEUMOTHORAX.

The distension of the cavity of the pleura by air may originate variously, but in most instances is consequent to the absorption of the serum effused in pleurisy. The long continuance of such effusion presses the lung towards

* Morbid Anatomy, p. 47.

MELANOSIS. 27

its root until permanent atrophy is established: if absorption is subsequently effected, the lung does not regain its bulk, and the serum is replaced by air. {Case 17.) In other instances the pleura is thus invaded from the bronchia, in consequence of ulceration. This affection appears also to be sometimes idiopathic.

HYDROTHORAX.

Dropsy of the Chest. — This name is given to idiopathic dropsy of the pleura, and must be cautiously distinguished from effusion from pleurisy, or from perforation consequent to an ulcer in the lungs.

The effusion in hydrothorax is limpid and without ftocculi; and the lung, pressed upon by this fluid, is collapsed towards the spine, and has its functions either wholly or partially suspended.

MELANOSIS.

Mclaiwsis is the name given by Laennec to masses of a black, or blackish-brown colour, occasionally found in the lungs, especially in tuberculous persons. This matter, according to the later views in pathology, is an excess of secretion of the pigmentum nigrum, modified no doubt by disease; in fact, it seems to bear much the same relation to the pigmentum nigrum that tuberculous matter does to the healthy albuminous secretions of the pulmonary tissue. Melanosis is mostly seen in amorphous masses, or irregular lamina?, as represented PI. III. fig. 2, or in black spots in the cellular tissue immediately beneath the pleura. (PI. XI. fig. 1.) It is sometimes encysted, and looks then not unlike a bronchial gland.* Pathologists also speak of this secretion in the fluid form, a modification I have not witnessed. Melanosis is essentially composed of the colouring particles of the , blood united with fibrine, (both of them in a particular state) three kinds of fatty matter, and a considerable quantity of phosphate of lime and iron. I am disposed to think that melanosis is less frequent in this country than in Europe. In the Parisian hospitals, Bayle met with it in about a twelfth part of his autopsies.

CALCAREOUS CONCRETIONS.

These substances are frequently observed in the lungs and bronchial glands. They are mostly encysted, (PI. III. fig. 2,) and give a gritty sensation in the fingers. Thenconsistence, however, is much varied, and they appear to be an intermediate link between tubercles and bony concretions. Analysis shows them to consist of ninety-six parts in the one hundred of saline substances, the remainder being animal matter. M. Andral considers them tubercles that have undergone an earthy transformation, an opinion that requires further proof.

OSSEOUS CONCRETIONS.

Bony masses are frequently secreted by the arteries in the lungs and their appendages: in the former they are mostly rounded, and enclosed in a cyst; in other instances they have a rough surface, by which they are firmly attach-

* See Carswell, on the Elementary Forms of Disease, &c.

DISEASED BRONCHIAL GLANDS 29

ed. In the bronchia, they are branched in the direction of the air-tubes. In the glands they are often grouped.

DISEASED BRONCHIAL GLANDS.

These bodies are particularly subject to hypertrophy: when cut their substance is pulpy, traversed by white lines. They often contain tubercles, and calcareous and osseous concretions, (PI. XII. fig. 2.) Again, they are occasionally softened, wholly or partially, into a yellowish, cheese-like substance.

Various other pathological conditions of the thoracic viscera, will be incidentally noticed in the course of the following pages.

Chapter II. Anatomy Of Tubercular Matter

Tuberculous matter presents itself in two very different forms, one of which is concrete, the other gelatinous: both of these varieties assume several different appearances.

MILIARY TUBERCLES.*

These are granules mostly of a yellowish or greenish gray colour, sometimes diaphanous, sometimes opaque, varying in size, under ordinary circumstances, from a figseed to a cherry-stone. They are either isolated or grouped, in the latter instance forming considerable masses; but if these be examined in their incipient state by reflected light, or with a glass, they are found to consist of an aggregation of the granules above mentioned.

These bodies are found on inspection to be extremely irregular in size and form; hence, also, in a state of aggregation, the masses may be rounded, ovoidal, angular, stellated, &c. (PI. I. II. III.)

Tubercles of this kind are sometimes in masses of a deep brownish-red colour, interspersed in others of a yellowish tint, giving the lung a marbled or mottled appearance. (PI. I. fig. 2.)

* Grandines of the older writers.

GRAY INFILTRATION. 31

It is obvious that pulmonary tubercles derive their gray colour from the pigmentum nigrum, as Laennec has supposed; whence they are often of a much darker tint in advanced life, as seen in those that surround the encysted abscess, PI. V. fig. 1.

When vast numbers of miliary tubercles reach the periphery of the lung, their rounded surface causes a partial displacement of the pleura; so that on removing the latter, the lung appears as if covered with a pustular eruption. (PI. II. fig. 1.)

CRUDE TUBERCLE.

This is called the second stage of tubercular matter, and certainly it is so in reference to the diaphanous variety, in which the transformation commences by one or more opaque points, and ultimately involves the whole mass. When the change is complete, the tubercular substance has a yellowish white tint, a texture approaching cartilage, but more humid and less compact,* and when cut into it is smooth and polished. (PI. II. fig. 3.)

It is certain, however, that tubercles often make their appearance in the opaque form, rendering the crude transformation, or rather the first stage of the suppurative process, much less obvious. (PI. I. fig. 2.)

GRAY INFILTRATION.

Matiere grise demi-transparente. (Louis.) — It is common to observe masses more or less considerable, of a light gray, translucent appearance, smooth, moist and

• Laennec, L'Ausc. Med. t. i. p. 22.

shining when incised, and seemingly dense, but breaking readily under the fingers. No trace of air-vesicles remains: here and there are seen opaque spots of various shades of white and yellow, marking the progressive transition into the suppurative stage. Sometimes the crude transformation simultaneously pervades the whole mass. So also vomicae form in various places, even while the surrounding portions still retain their original morbid characters. (PI. III. fig. 1.)

This variety, like the following one, manifestly results from an abundant secretion of tuberculous matter through a large portion of parenchyma at the same time: masses very similar in appearance, however, result from the slower process of miliary accretions, especially when the latter assuming an angular form, coalesce into a uniform mass, as may be inferred from PI. II. fig. 2.