380 CI^APTER XXXI. 



Brain (Hamilton^ Jonrn. of Anat. ami Phy.iiol., 1878, 

 p. 254).— Put into— 



Muller's fluid .... 3 parts 



Methylated spirit .... 1 part 



in an ice-safe. Change the solution in a fortnight or three 

 weeks ; or if it is found that the reagent has duly penetrated, 

 remove to — 



Bichromate of ammonia . . 1 grm. 



Water 400 o.c, 



for one week. Then change the solution to one of 1 per cent, 

 for one week, and 2 per cent, for another week, or longer. 

 The pieces may be kept permanently in solution of chloral 

 hydrate, twelve grains to the ounce. 



Entire Encephalun (Deeckr, Journ. Roy. Mic. Soc, 1883, 

 p. 449). — Bichromate of ammonia in | to 1 percent, solution, 

 according to the consistence of the brain. If it is soft he 

 adds, say, ^ to yV P^r cent, of chromic acid to the solution, 

 and always ^ to -^ of the whole volume of alcohol. 



Enceplinlon (M. Ddval, Robin's Journal de I'Anatomie, 

 1876, p. 497). — Bichromate of potash 25, water 1000 ; change 

 after twenty-four hours, and again after three or four daj's. 

 After two or three weeks place in chromic acid of 3 per 1000, 

 change every day for the first week and after that every 

 eight days until the middle of the second month. The pre- 

 parations must remain at least two months in the chromic acid. 



Obt[I [Berlin, hlin. Wochenschr., 1896, No. 13) takes 

 Formol-Miiller (§ 113), changed every few days. Small 

 pieces may be sufficiently hardened in a few days in a stove. 

 This is now very popular. 



BoNviciNi [Zeit. ivi.is. Mil-., xxvi, 1909 p. 412) puts 

 entire brains into 10 per cent, forinol (first injected through 

 the carotids or into the ventricles) for six to eight daj's, then 

 slices of it (in the dark) into 4 parts bichromate of potash 

 and 2"5 parts sulphate of chromium in 100 of watei', changed 

 weekly for two months (hemispheres), or twelve to fourteen 

 (lays (medulla and pons), or five to six days (cord). 



Rawitz [ihid., p. 338) puts fonnol material for exactly 

 five days into alcohol with 10 per cent, of tinctura iodi 

 P.G., then for eight to ten into satui'ated solution of bi- 

 chromate, changed after the first dfi.y, then into 05 per cent, 

 alcohol in the dark for three days. 



