Preparation, etc., of Frozen Anatomical Sections. 353 



XVII. On the Preparation and Preservation of Frozen Ana- 

 tomical Sections. By J. Symington, Esq., M.B., F.E.C.S.E., 

 Lecturer on Anatomy, School of Medicine, Edinburgli. 



(Read 16th February 1881.) 



The method of anatomical investigation by means of frozen 

 sections offers many advantages over the ordinary methods of 

 dissecting, in the determination of the exact position and 

 relations of the viscera and other structures. 



By the researches, in this manner, of Pirogoff Braune, 

 Luschka, Henle, Legendre, Eiidenger, etc., our knowledge of 

 the topographical anatomy of the human body has been 

 rendered more exact, and many erroneous ideas have been 

 dispelled. As the plan admits of being applied to the inves- 

 tigation of many undetermined points in comparative anatomy, 

 and as only vague directions are given in the various works 

 on topographical anatomy regarding the mode of preparing, 

 examining, and preserving frozen anatomical sections, I 

 thought it might be useful to bring before this Society a more 

 detailed account of the various points which my own experi- 

 ence leads me to consider as of special importance. 



The animal or part which is to be frozen, unless very small, 

 should be first injected with preserving fluid and the arteries 

 filled with lard coloured with vermilion. As a preserving 

 fluid an arsenical solution acts admirably, but care should be 

 taken not to inject or previously immerse the animal in 

 methylated spirit, as this would interfere with the freezing 

 process. 



If the sections are to be made in relation to any bony pro- 

 minences, these should be marked on the skin previous to 

 freezing, as when frozen they will not be distinguishable by the 

 feeling from the soft parts. The animal should then be fixed 

 in a watertight case, and great care must be taken that the 

 body is not distorted in any way by pressure. For animals 

 of moderate size, sach as a cat or small dog, an ordinary fish 

 kettle with a well-fitting lid answers admirably ; for those of 

 a larger size a tin case, as near the size of the animal as pos- 

 VOL. VI. z 



