Anatomical manipulation, or, The methods of pursuing practical investigations in comparative anatomy and physiology : also an introduction to the use of the microscope, etc., and an appendix

Front matter

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A N A T 0 M I C A L MANIPULATION.

LONDON :

Preface

referred to, though well adapted to the time at which it ap¬ peared, is now in many respects useless to the inquirer in the wide and interesting fields of Comparative and Structural Anatomy.

The want of some guide in these researches having been long felt by the writers of the following pages, and it is presumed by others also engaged in similar pursuits, they were happy to meet with such a one in the excellent “Traite Pratique et Tlieorique d’ Anatomic Comparative” of M. Straus- Durckheim (Paris, 1842), and the idea at the same time sug¬ gested itself that they should avail themselves of the extensive zootomical experience of that author to supply the above deficiency in this country. With this view they have fol¬ lowed his plan more or less closely in the First and Third Parts, condensing and translating his matter every where, and making such additions and alterations as they held to be needful, while the whole of the Second Part has been written anew. They would fain hope that they have thus produced a work, which will be found useful in smoothing the way to students entering upon the studies of Comparative Anatomy and Physiology.

Parts I and II, prepared by Arthur Henfrey, treat of Mechanical Arrangements and the Microscope.

Part III, by Alfred Tulk, contains directions for Dis¬ secting and Preserving the several systems of organs.

PREFACE.

Vll

In addition to the treatise before mentioned, the following works have been consulted : —

Directions for Collecting and Preserving Animals.

Royal College of Surgeons, London.

Owen’s Lectures on the Invertebrated Animals, 1843.

Penny Cyclopaedia — Article, Microscope.

Pole’s Anatomical Instructor, 1813.

Todd and Bowman’s Physiological Anatomy, Part I

In conclusion, the Authors have to express their thanks to Prof. Edward Forbes and Dr. Griffith for their articles appended to this work ; as also to Dr. Willis, for allowing them to avail themselves of the extracts from Prof. Wagner’s Physiology.

THE AUTHORS.

London , Dec. 1843.

Sect. 4. — Radiata, Entozoa . 382

CHAP. XIV. — Organs of the Senses. XVI

CONTENTS.

Page

Sect. 2. — Articulata, Crustacea . 401

Conclusion . 403

Appendix . 405

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M E C H A N I C A L A R R A NGEMENTS.

CHAP TEE I.

APARTMENTS, &c.

SECT. I. — Dissecting Rooms, &c.

1. Animals may be divided in relation to the methods employed for their dissection, according to their size, into four classes, namely, very large animals, such as the horse, the ox, and creatures above that size ; those of ordinary dimensions, as man, the small Ruminants, &c. ; moderately small species, as the cat, rabbit, and most birds ; and, lastly, those minute objects which require the aid of magnifying instruments in their investigation. The first two of these classes, from their great bulk, the mass of offal, and the putrid vapours to which they give rise, will obviously need a separate apartment distinct from the private study of the anatomist ; while it is in the latter, that the third, and more especially the last class of objects, in dissecting which the microscope and other delicate contrivances must be used, may be most conveniently examined.

2. The rooms or halls appropriated to the dissection of very large animals, as is the case in veterinary schools, should be situated upon the ground floor, and should open externally by a gate, so that any huge carcase,

b 2

PLATFORMS AND TABLES.

even that of an elephant, may be brought in upon a waggon. They should he so exposed as to he free from damp ; paved, and well drained, perfectly lighted hy a number of windows, either from above or on both sides, and rather lofty, to allow the gaseous vapours to ascend above the heads of those dissecting, and escape by means of tourniquet ventilators, placed near the top of each window.

The extent of the hall, taking a certain number of animals to be dissected at once, may be thus calculated : the body of a large ruminant occupies with its plat¬ form a square space of nearly 9 feet, and the table for preparing its voluminous organs upon, about feet; so if three platforms be arranged in a row down one side, and four tables along the other, the length of the room would be 30 feet, and the width 18 feet. Dur¬ ing winter, two or more stoves, provided with coppers for heating water or injections, may be placed in the middle of the apartment, so as to distribute the warmth equally throughout.

The moveable articles, which a large hall like the above should contain, are some cupboards with shelves, at each end, some platforms, tables, and wooden chairs ; with sundry others, such as diagram boards, drawing frames, and disinfecting apparatus.

3. Large animals are usually dissected in the veteri¬ nary schools upon the ground, or on the vehicles in which they have been brought ; but the greatest incon¬ venience is thereby felt, from the inability to turn diffe¬ rent parts to the light. This, however, may be remedied by the use of platforms, of sufficient size to support a

DISSECTING TABLES.

horse, or ox ; the opportunities of dissecting ]arger sub¬ jects, such as elephants and rhinoceroses, being too rare to call for any special contrivance of the kind. These platforms (fig. 1) should consist of a horizontal piece of timber 8 feet 4 inches long, by 3 feet wide, and 1 6 inches from the surface of the ground, covered with a layer of small planks, and slightly inclined towards one end, with a gutter in the middle to facilitate the escape of fluid, by a hole at A, to which a tube is at¬ tached. The wood work or base of the platform has the form of an X, the main beam (B C), from 7 to 8 inches wide being placed dia¬ gonally across, while two others of equal strength (D E, F G), are simi¬ larly disposed, but do not join in the centre, to avoid weakening the principal stay, upon which the platform is to revolve by a pivot fixed into the floor, and penetra¬ ting the plank B C at O. More slender stays (H I J K), unite these diagonal branches, and beneath the extremi¬ ties of the latter are perpendicular iron castors, about 7 inches in diameter, to assist the rotatory motion of the platform. Two of these are rather shorter than the others, to give the platform a gentle slope towards the drainage opening (A). If the subject be too large for the platform, its surface can be increased by placing the head, with part of the neck, upon a plank thrust under the body.

4. The dissecting tables should form a row opposite

Eg. i.

THE STUDY.

the platforms, at a yard distance from the wall, and with a space of 2^- yards between their centres. They should be somewhat less than those ordinarily used in dissecting rooms ; about 1 yard long by f- wide, as bodies only of middling size, as those of a sheep or goat, or fragments of large animals, are dissected upon them. Above each platform and table a rope with pullies should be attached to the ceiling.

5. The same general principles of construction will apply to ordinary dissecting rooms, as to the large halls. The best kind of dissecting table is made in the form of a slightly concave platform covered with lead or zinc, turning upon its centre, which should rest upon a round table, with its four legs fastened to the floor. The apartment is to be heated, like the preceding, by means of stoves, in number proportionate to its extent.

G. The study of the anatomist, is the place in which the latter engages in the dissection of animals of mode¬ rately small size, and those below it ; it serves also for other kinds of work, such as microscopic observations, drawing, and the preparation of books for the press. This apartment should differ therefore considerably from the dissecting rooms spoken of above. It ought to have a south aspect, that the objects under dissection may be directly illuminated by the sun ; the window should be without embrasure, so that the table may be placed quite against the glass. Each side of the window should be furnished within with a white and thick calico blind, to prevent the passage of a glaring light, where objectionable. These blinds will cover with their shadow the whole dissecting table, with the exception

LIGHT.

of the spot where the specimen is, upon which re¬ searches are being made ; and as the stream of light which passes beneath them is, usually, still too large, it may be diminished by means of screens, placed either upon the table, or against the window, and which are adjusted one behind the other according as is necessary, so as to allow only of a sufficient ray of light imping¬ ing upon the object, whilst all the rest of the table is in shadow ; this admits of the drawing or writingpaper being so placed, that the light which falls upon it does not affect the eyes. Coloured, and especially green, blinds might have the advantage of relieving the sight, by shedding a softened tint upon all the objects placed upon the table ; and this would be very impor¬ tant to the observer, who often fatigues his eyes con¬ siderably in the examination of minute animals, or in making microscopic observations ; but these tints, com¬ municating also to the paper on which he draws a particular colour, injure the effect of the designs, to a great degree, when viewed afterwards by a white light.

7. Above the middle of the dissecting table there should be fixed to the ceiling an iron hook, to which different objects, and especially the injectory, which will be described further on, may be suspended. The study of the anatomist, serving at once as a laboratory and an ordinary dwelling, contains a greater number of moveables than the dissecting rooms, as well as part of his library, and many other objects subservient to his researches, such as a lamp, drawing table, &c.

8. As it is generally admitted for the facility of work, that objects to be drawn, or the microscope,

MACERATING ROOM.

should be lighted from the left, the dissecting table should be so placed against the window as to receive the light from that side. A convenient size for this table will be, for example, 3 feet long by 2 feet wide. As to height, it must vary according to that of the person who makes use of it, and should be such, that when seated, the microscope can be easily looked through, with the hands resting comfortably upon the stage, in the ordinary position of dissection, a condition quite essential in prosecuting anatomical researches with this instrument.

SECT. II. — Workshops, &c.

9. Macerating Room. — In every large establishment, where many skeletons are prepared, it is necessary to have a separate place for macerating bones. This may be some cellar, chamber, or a simple shed ; but care must be taken that it is not so exposed to the sun, that the latter strikes upon the macerating troughs ; a dark situation, therefore, is the best, but not a cool one, lest putrefaction be retarded. These conditions, so essen¬ tial to a macerating locality, are required to prevent green matter or mould from developing itself in the troughs, more especially the former, which attaches itself to the bones at the bottom of the water, incrusts them, and imparts a black or yellow tint, which can never be got rid of. This happens when the trough is exposed to the open air, and chiefly to the sun : even

TROUGHS.

when there is no production of green matter, the flesh itself turns brown and tinges the bones.

The moveables in the places of maceration are simply some troughs, in which bones are macerated, and pails for conveying water.

10. Troughs. — These are cylindrical vessels of all dimensions, the large size in wood, the middling in earthenware, and the smallest in glass. The wooden ones should be of deal, ash, or any other timber which does not lose colour ; not of oak or walnut, as they impart a black colour to the water, especially if it con¬ tains a little iron. In this case the gallic acid of these woods forms with the iron a perfect ink, which pene¬ trates the bones, and so colours them that they cannot be whitened ; and even if no iron is present in the water, the tanningTenders the latter perfectly black, and colours the bones grey. The best troughs are those of earthen¬ ware, but they can only serve for small animals. The)’’ can be kept much cleaner, and freed better from green matter and mouldiness than the wooden ones, in which, when these matters are once developed, there is the greatest difficulty in destroying the germs which incrust the timber. It may however be effected by reversing the trough over a fire with live coal, and heating it nearly to ignition ; boiling water does not destroy them.

The earthenware pans may be also well heated by fire to destroy these germs ; and the glass ones, generally the smallest, can be rinsed out with a concentrated acid, after being well washed, so as to leave nothing but the germs for the acid to act upon.

DRYING PLACE.

The troughs should be, if possible, sheltered from a current of air, which causes the evaporation of the water, in which case this latter must be renewed at intervals. To prevent this inconvenience, the troughs should be well covered up, and during the time of ma¬ ceration be meddled with no more than is necessary, for fear of diffusing the fetid odour.

11. Drying Place. — There should be near to the macerating room one exposed to the sun for drying and bleaching the bones. A part of this place, which is best located in a garden, should be open, so that the bones may be exposed as long as possible to the sun, dew, rain, and snow, the alternate vicissitudes of which produce the required bleaching.

Another part of the drying place should be a cham¬ ber provided with a stove, in which every kind of pre¬ paration may be quickly dried. The methods employed will be described in the chapter upon the osseous sys¬ tem.

12. In the external part of the drying place should be placed several tables with raised borders, so that the objects placed upon them may not fall off, and having at their lowest extremity a small hole by which the water may drain off. The upper part of these tables may be of solid wood, laths, or metal.

In this room there should be, besides the stove, some tables and places for hanging up preparations, and se¬ veral basket-work frames which may be suspended from the ceiling, or laid upon sticks, and serve to dry diffe¬ rent specimens upon.

13. Boxes for Insect-made Skeletons. — These

WORKSHOP.

boxes are little laboratories, in which the agency of different insects, but chiefly ants, is employed for mak¬ ing the skeletons of very small vertebrated animals. Their size should be two inches each way, seldom more, and they should be made of some wood which does not suffer from moisture, and should shut as close as pos¬ sible. They may be also of tin or zinc, but their outer and inner surface should be unpolished and even rough, so that the insects may travel over them, in going out, and coming1 in. In their sides there should be a great number of holes just large enough to let a single ant pass through, but not to admit of its conveying away with it any small ossicles, which they never fail to do if not prevented. If these boxes are destined for the ope¬ rations of dermestes, ptinus fur, or anthrenus, they may be of any substance, as card, since these insects gnawing only the dry organic substances preserved in the interior of houses , there is no need of their being exposed to the wet, while those in which the ants work enclose fresh animals, and should be placed near the nests. The dermestes and ptinus seldom quit the boxes.

14. Workshop. — An establishment devoted to the study of anatomy, and amongst others, to the art of making skeletons, must necessarily have a workshop, provided with a sufficient number of tools ; since it is there that the pieces of metal, wood, leather, &c., re¬ quired in mounting skeletons, are finally adjusted, where injections are prepared, and the vessels for preserving anatomical preparations sealed up.

This work-shop should contain a small lathe-drill for piercing the bones. There should also be a fire-place

GLASS-CUTTING MACHINE.

for operations requiring its use, and lastly a cistern for the supply of water ; while here also the stores, jars, preserving fluids, injecting matters, &c., are kept.

15. Tools. — In addition to the instruments already noted, there should be a large table, a small bench, with a vice and anvil, a grind- stone for whetting large instru¬ ments, tools belonging to the lathe, a small drill- bow with drills of different sizes, files, rasps, gravers, chi¬ sels, different flat and cutting pincers, pliers, hammers, a mallet, punches of different sizes for labels, saws, &c. Besides these ordinary implements, it is convenient to have some others, which if not indispensible, are at least, very useful ; they are as follows : —

16. Machine for Cutting the Glass Plates used as Covers to the Glass Jars. — The jars in which ana¬ tomical preparations are preserved, are occasionally closed by plates of glass hermetically luted to them. These plates, generally round, are difficult to cut with the hand, except a wooden pattern of each size is provided, which would be almost endless work, and would cost more than a windle which can be used for cutting the plates. This machine consists of a board 1 foot 8 inches long,

by 8 inches or a little more in width (fig. 2, A). On the middle of this, which serves for its sup¬ port, is a round disc of wood (B) about 1 foot 4 inches in diameter, turning on its centre. Towards one extremity of the hoard, at a little distance from the edge of the disc, there is fixed an iron hinge (C), in which the extre-

DRILL STOCKS.

mity of a square iron rod (D) plays, so that it can be raised and lowered in order to be placed parallel to the disc, over the centre of which it passes, and is prolonged beyond it ; at the other end it rests in a second hinge, similar to the first (E), but without the pin. This rod thus placed must be parallel to the disc, and about half an inch distant from it ; upon it slides a small copper car¬ rier (F), bearing below a diamond for cutting the glass, and above, a pressure screw for fixing it upon the rod. Around the centre of the disc, and upon it, are traced a great number of concentric circles distant from each other one quarter of an inch, to point out the size of the plates to be cut, and at the same time to assist in adjusting the piece of glass employed. To use this windle, the piece of glass is cemented upon the centre of the disc, and the carrier, which supports the dia¬ mond, fixed in such a manner that the latter corres¬ ponds to the circumference of the circle, the size of which it is wished the plate should be ; the rod is lowered upon the plate of glass and kept there by the left hand, so that the diamond rests slightly upon it, then making the disc turn round with the right hand, the glass is borne along with it, and cut by the dia¬ mond.

For cutting plates which are not round, as very often happens, the outline of the shape to be given is traced upon a sheet of paper, the piece of glass placed above it, and the plate cut freely with the hand raised, following the figure placed beneath.

17. Drill Stocks. — These are of two kinds, one of which can be fixed by screwing into the table, and be

LAMP FRAME.

set in motion by a bow. It is with the assistance of this instrument that solid bodies of moderate size are pierced, and the strongest drill which fits in may be about a line in thickness. The second sort used for piercing very fine holes, such as might be made with a needle, is so contrived as to be set in motion by the fingers, between which the handle of the instru¬ ment rolls.

The fine drills have the form of those used for pier¬ cing metals, or are simply round or square pointed, when they are to serve for piercing very fine bones.

18. Lamp Frame. — As it is often necessary to keep liquids at an elevated temperature, it is very useful to have a small spirit lamp frame, upon which a vessel containing the substance to be heated may be placed. This apparatus may be of any shape, but the most con¬ venient is that in which the frame, on which the vessel is placed, is formed by a circle, 4 inches or more in diameter ; from this proceed three tongues directed to¬ wards the centre, leaving a space of about ^ of an inch, so as not to intercept the flame. The lamp placed be¬ neath the middle of the frame should be so constructed, that by means of a screw, the wick may be raised or lowered to regulate the heat as required.

19. Nrosogen. — An apparatus for artificial incuba¬ tion. Anatomists in pursuing investigations, involving the stages of development of the fcetus of birds, make use of this instrument, but every one having peculiar notions as to its modifications, it will suffice to give the general principles here. The principal conditions which appear to be required, are an equable heat, some degree

NEOSOGEN.

of moisture, and free access of air. The apparatus generally consists of a cylindrical vessel of tin having double sides, the intervening space being tilled with some non-conducting substance ; the bottom is perforated by tubes allowing the air to enter ; the eggs are kept on trays supported by little columns, so as to allow of their being placed one above another. The ' whole has a wooden cover (pierced with holes), and is heated by a spirit lamp placed beneath a wide tube, closed above, which passes up the middle of the apparatus. It must be kept where it is not exposed to a current of air, and the eggs should be marked with ink as they are put into the apparatus, and turned every two or three days.

It is obvious that the foregoing extensive array of appliances is only given to show what should be done when circumstances allow of it, and in a large establish¬ ment ; but it is hoped, that the student will be able to select those portions best adapted to his means and the particular direction of his investigations.

It is with this idea that so general and comprehen¬ sive a view of the subject has been taken.

Chapter II. Instruments

20. In addition to instruments for actual dissection, ana¬ tomists make use of certain others which prepare the objects of dissection, in such a manner that the former act to the greatest possible advantage. The most im¬ portant among these, are those for injecting the different vascular structures, so as to display them with greater distinctness.

SECT. I. — Injecting Instruments.

21. Swammerdam’s Syringe. — The instrument usually employed for injections is the syringe contrived by Swammerdam. It is of the ordinary shape — a cylin¬ drical body, with a piston working in it to drive the injec¬ tion into the vessels ; but as it would be difficult to fasten the tube to the vessel, if the former were fixed to the body of the instrument, this is provided with a second tube fitting over the other, to which it is adjusted when necessary, by a bayonet catch or other simple contrivance, a screw being objectionable for obvious reasons. This second tube is to be fixed by a ligature into the vessel to be injected, and as these vary, the instrument is

CHARRIERE S PISTON.

generally provided with several of them, with different sized nozzles. The inner tube (which forms part of the syringe itself) should be provided with a cock to pre¬ vent the escape of the liquid. The piston rod commonly has a large button at its upper extremity, which the operator places against his breast, in order to push with greater force and regularity. The ordinary syringes used at the medical schools hold about two quarts, which is sufficient to inject the principal trunks.

22. When these syringes are of small size, they ought to be bored very truly, in order that the piston may slide with equal freedom in all parts, so as to allow the operator to feel the slightest resistance to the pas¬ sage of the fluid, and thus to warn him to moderate his efforts when there is danger of rupturing any vessel ; and, on the other hand, that it may not be loose in places and produce jerks. The piston ought also to be so perfectly adapted, that the liquid injection cannot get behind it, and its thickness should at least equal its diameter. The mass of this thickness is ordinarily made up of discs of felt, which may be more or less compressed by means of the screw which receives the inferior metal plate of the piston.

23. M. Charriere has invented another kind of pis¬ ton, infinitely better, which slides much more

freely, and does not allow the injection to escape. It also consists of two parallel discs (fig. 3, A, B), placed at some distance apart, and rather less than the internal diameter of the syringe ; instead of the discs of felt, there are two of soft leather (C, D), placed in the middle, in

c

IS

SYRINGES.

contact, their diameter being half as much again as the bore of the syringe. The intervals between these discs and the metal ones are bound with packthread, only leaving space enough between them and the wralls of the pump to lodge the leather discs, which are turned back in the form of a hood over the packthread on each side, thus applying themselves to the inside of the syringe. When the piston is pushed down, the liquid endeavours to make its way towards the upper chamber of the syringe, and entering the bell- shaped cavity formed by the leather disc, it presses the edges of the leather against the wralls of the pump, and thus prevents its own escape. In drawing up the piston a similar action takes place, the air being substituted for the liquid. In both movements the piston slides with the greatest facility.

24. Every time an instrument is used it should be taken to pieces, and all parts thoroughly cleaned; and should be placed separately, if possible, in the box where they are kept, to prevent any parts becoming fixed together by oxydation. To clean greasy por¬ tions, spirit of turpentine is used ; for others, hot water or alcohol, according to what has been used as the vehicle of the injection.

25. In small syringes the piston-rod should end in a ring, and the cap of the syringe (through which it passes) should be provided with a ring at each side. Placing the first two fingers in the latter, and the thumb in the ring of the piston rod, a very regular and safe motion can be communicated to it. It has been said, that the body of the pump should be fixed to the canula

INJECTING PUMP.

by a bayonet catch, but it may simply slide into it. To prevent their separation in large instruments, the canula should be furnished with two ears, with holes in them, to attach a loop of string, which passes round the fingers of the hand that supports the pump.

26. As the same quantity of matter may have to be injected through different sized vessels, the instrument should be provided with several canulas of different calibre. One to inject the aorta of man should be about half an inch, external diameter, the others may gradually diminish in size, until the smallest is about one- eighth.

The large canulas should have a cock, in order to retain the injection until it sets , at their upper part should be two circular grooves to lodge the ligature of the vessel. The smaller sizes need only be furnished with a cork, and one groove will be sufficient.

By placing a flexible tube (about 20 inches long for a syringe holding a quart) between the pump and the canula, the instrument may be supported on the table or basin where the subject is placed, by which means much fatigue is avoided, and a more regular mo¬ tion obtained.

27. Injecting Pump. — The apparatus about to be described, may be very advantageously substituted for that of Swammerdam ; it not only allows the slightest resistance to be appreciated, but the injection may be continued to any extent without interruption in charg¬ ing the receiver.

This pump is formed of a cylindrical brass basin (fig. 4, A A), in the centre of the bottom of which is screwed.