10 INTRODUCTION. 



t 



are not being dissected. A number of dogs can 

 be kept in good condition in this way with but 

 little expense, especially if it is possible to remove 

 the intestines, or at least the large intestine and rec- 

 tum, after the first day. This method of preserving 

 the animal has the great advantage of not decolorizing 

 any of the tissues, and furthermore prevents the sour 

 odor which soon comes on after using preservative 

 liquids. If it is not possible to make use of this 

 method, and it is necessary to keep the animal for 

 some time, recourse must be had to some of the usual 

 preservative liquids. Immersing the dog in alcohol 

 will keep it from decomposing, but leaves it in such a 

 bad condition for dissecting that it is not to be recom- 

 mended. Wickerscheimer's liquid injected into the 

 arteries after having previously washed out the blood 

 with 0.6^ sol. of NaCl is highly recommended, though 

 my experience with it has been unsatisfactory. The 

 formula for this liquid is as follows : Dissolve in 3 

 litres of boiling water 100 grms. of alum, 25 grms. of 

 common salt, 12 grms. of potassium nitrate, 60 grms. 

 of potassium carbonate, and 20 grms. of arsenious acid ; 

 after cooling add 1^ litres of glycerine and I litre of 

 alcohol. A liquid which I have tried but few times, 

 but which has given satisfaction, is made by mixing 

 one part of glycerine with two parts of a 2^ solution 

 of corrosive sublimate, and adding to this mixture 

 crystals of chloral hydrate in the proportion of 2 grms. 

 of chloral to each 100 cc. of the liquid. This liquid 

 keeps the animal pliant, does not destroy the color, 

 and seems to bring out the nerves more distinctly. 



Necessary Dissecting Insinnucnts. — Each student 

 should be provided with a small case of dissecting in- 

 struments containing at least the following things: 



