surfaces of which are painted. From their large size Articles. we Original they show more than the originals to a class, but and for METHODS OF TEACHING ANATOMY AT THE have the latter at baud for study small classes, HARVARD MEDICAL SCHOOL: ESPECIALLY as of graduates. We have also good models of sections CORROSION PREPARATIONS.1 through the body from Leipzig. This method of frozen sections is the of BY THOMAS DWIGHT, M D., teaching anatomy by growth Parkman Professor of Anatomy. the last twenty-live years or so. It is longer than that since its use in and The ¡dea of a of the in by Pyrogoff Russia, by Legcndre holding meeting Academy in not so since 1 showed at Bowdoin this is to mind a one. It France, and long building my very happy gives the first frozen sections made in Now me the of of our methods of College England, opportunity speaking in the anatomical and of the treasures and probably United States. instruction, displaying of instruction used in of our museum before an audience to Another method occasionally appreciative of the whose would be other- this department, chiefly to show the base skull knowledge they hardly brought and the of the is in wise. It is one of the of general plan braiu, modelling cluy greatest discouragements before the class. One need not be an artist to those who labor to establish museums of a somewhat acquire with a little skill to make models restricted nature, that it takes so many years for the practice, enough which ideas in a manner. merits of a collection to be known. Few visit our convey striking I come now to the second of that museum besides those to the School. part my subject, belonging of which be purpose is to of methods preparations, though they may brought My to-night speak solely before the have their home in the museum. In of anatomical instruction, and I divide my remarks class, the museum often a to the into two no very delinite line. Europe gives reputation purls, separated by school and there are which are known The lirst shall what may be called the appa- preparations comprise anatomists as rare coins, stones, ratus of instruction, used in the lecture-room ; among just precious chiefly and works of art, are familiar to collectors who may the other which, used more or less preparations though never have seen them. before the have also an intrinsic scientific worth class, Warren founded John C. and to the museum. Our Museum, by Warren, belong especially has indeed a name museums in this ; To with the former : Our collection of charts among country begin but to tho labors of the late Professor J. IJ. S. is a fine one. I have no time to dwell on it, but de- owing the has so far sire to show some of of bones Jackson, pathological portion outstripped these diagrams copied the from Ilolden's with red and blue lines the anatomical one proper as to have given stamp Osteology, This is shown the the and insertion of muscles. to the museum. pretty clearly by marking origin They of the Warren Anatomical are most useful for and will I am catalogue Museum, pre- teaching, have, sure, Dr. Jackson and in 1870. new interest this as have an addi- pared by published to audience, they the series of value to when it is known that are the Eight years ago, almost only prepara- tional me, they which handiwork of venerable Dr. tions illustrating normal anatomy could be my predecessor, Holmes, a arterial dissec- made in the later of his We have shown with satisfaction, was set of years professorship. Dr. R. M. some here a similar series on the bones tions by Hodges. Though thirty themselves, painted old still their value. Dr. Newell, an assistant in the Anatomi- years they keep by formerly Our collection of frozen sections is but as I cal These rather rep- large, Department. large, diagramatic have few are on exhibition. As resentations of parts of the skeleton, are used in trans- said, comparatively for the bones I say little, there is a slates on which the soft parts, muscles, vessels, although great parent deal to We have an unrivalled etc., be sketched before the class. say. probably display nerves, may rapidly of series of thin slices of bone to show the wondrous Our collection of models is a very good, indeed, an of nature's architecture. Suffice it to that ^ one. Ilesides the standard ones in tracery say exceptional, papier- we have of sections iu order mache which are seen we have one in sets arranged regular everywhere, the whole of the end of a bone cut in a cer- wood of some of the cranial bones and the bones of showing other it cut at the made under the direction of Dr. Holmes, and tain direction, while series show right face, to tho of the former set. There are also we have these models of the bones made of angles plane enlarged series cuts of certain bones in paper, Mr. Emerton, to my criti- showing corresponding blotting by subject and in several animals.2 We have also a col- cisms, which for size, and accuracy, are man lightness truly lection to show anomalous structures in bones, aud remarkable. These of the vertebra! are enlarged six and these others of the another, probably very nearly an unique one, to teach times (linear measurement) further bones aud of the three times. the range of individual variation and to the long shoulder-girdle, of the relation between the of the bones Here are tho bones of the separate, and here study shape leg joined and the of the individual ; but the time has not the interosseous membrane, which allows them to figure by come to on this I cannot leave the de- be shown as one as are. Here report subject. apparatus, they really of without to the val- are some of models the relation partment osteology alluding very Cunningham's showing uable addition to our of a few between skull and brain at different ages. array skulls, presented The of the of frozen sections years ago by Dr. J. Collins Warren. development system I to of our sets as a means of anatomy, has desire, however, speak particularly teaching necessarily of as it is evident with it new Wo have frozen corrosion preparations, especially brought models. many or who sections in the school of which but few in the from the recent writings of one two gentlemen figure have busied themselves in this matter, that our collec- to the and expense of satis- museum, owing difficulty tion is not known. A corrosion is We have two large models in widely preparation factory mounting. one in which the vessels, the ducts, or cavities of or- plaster, home-made, chiefly by Dr. Muiiro, one of the as of the ear or heart, are filled by a fluid which arm and one of the leg, which are cut into slices, the gans, will harden and so give the shape of the vessel or 1Read before the American Academy of Arts and Sciences, April 8, 1891, at the Harvard Medical School. I Soe appendix. " The Boston Medical and Surgical Journal as published by The New England Journal of Medicine. Downloaded from nejm.org at UNIVERSITY OF MELBOURNE on March 29, 2016. For personal use only. No other uses without permission. From the NEJM Archive. Copyright © 2010 Massachusetts Medical Society. cavity. After that the organ is corroded or digested be used. The soft parts may be destroyed by acid ; so as to be completely destroyed, and all that remains but Dr. Mix ter has invented a digestive fluid which is the cast of the cavity. Most beautiful and most in- is better. Here is a truly admirable injection of tho structive .preparations are obtained in this manner. arteries of an entire leg and foot. The almost capil- We have here corrosion preparations of three different lary net work at the balls of the toes is finely shown. kinds each of which has its own merits. Here, also, is a kidney in two colors, so completely The first in order of making are these in brilliant injected that only the surface is visible. The defi- colors by a method taught me by Professor Itiidinger ciencies of this method, which in some respects gives of Munich, over twenty years ago, which differs from the most perfect results, is that the large vessels are that of Ilyrtl, with whose name these preparations not distended, and that the preparations are preserved are generally associated. The injecting mass is a in iluid. I may say that all the celloidiu preparations mixture of rosin and white wax colored with paint are by Dr. Mixter, and so are all the metalic ones dissolved iu balsam of copaiba. After the injection with, I believe, one exception. The wax and rosin the. organ is destroyed by hydrochoric acid and water. ones are, with a few exceptions, my own work. When the injection alone is left it is given a gloss and Believing that one of the first duties of a professor greater strength by pouring over it repeatedly a solu- of anatomy, apart from actual teaching, is the forma- tion of gelatine in acetic acid. The preparations are tion of an anatomical museum, I have devoted myself certainly beautiful, especially when several vessels are to that end. Whatever success has been gained is injected in different colors, as this kidney, with a red due in great measure to my assistants, both past and artery, a blue vein aud a yellow ureter, and this liver present, above all to Dr.