NEUROLOGICAL METHODS. 385 



for cutting ; they may be kept permanently in solution of 

 chloral hydrate, twelve grains to the ounce. 



689. Entire Encephalon (DEECKE, Journ. Roy. Mic. Soc., 

 1883, p. 449). Bichromate of ammonia in to 1 per cent, 

 solution, according to the consistence of the brain. If it 

 happens to be soft he adds say % to T ^ per cent, of chromic 

 acid to the solution, and always ^ to ^ of the whole volume 

 of alcohol. 



Further details in previous editions. 



690. Encephalon (M. DUVAL, ROBIN'S Journal de I'Anatomie, 

 1876, p. 497). First Method. Place the fresh tissues in 

 solution of bichromate of potash 25, water 1000 ; change 

 the liquid after the first twenty-four hours, and again after 

 three or four days. After two or three weeks place the 

 preparations in chromic acid of 3 per 1000, change the 

 liquid every day for the first week, and after that every 

 eight days until the middle of the second month, after 

 which time it is no longer needful to change the liquid. 

 The preparations must remain at least two months in the 

 chromic acid ; the longer they remain in it the better. A 

 few fragments of camphor should be added to the liquid in 

 order to prevent the growth of mould. 



691. Encephalon (Fisn, The Wilder Quarter- Century Boole, 

 1893, p. 393). 



Water 400 c.c. 



95 per cent, alcohol . . . 400 



Glycerin 250 



Zinc chloride .... 20 grms. 



Sodium chloride . . . . 20 ,, 



Immerse in this, filling the cavities of the brain with it, and 

 if practicable also injecting the blood-vessels with it, for 

 about three days, then transfer for a week or more to a 

 mixture of equal parts of the fluid and 70 per cent, alcohol, 

 and finally store in 90 per cent, alcohol. 



692. Formaldehyde. For formaldehyde in general, see 

 104. 



WEIGERT (Beitr. zur Kenntn. d. normalen menscklichen 



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