APPENDIX. 491 



The stronger solutions employed in the final stages of 

 hardening or preservation should be replaced at intervals. 

 In the case of preparations which have been transferred 

 from acid solutions, the spirit must be repeatedly changed, 

 until all excess of acid is removed. 



Preparations of nervous tissues or sense-organs, if 

 treated with alcohol, should be put at once, when quite 

 fresh, into strong spirit. 



3. Ammonic bichromate, Solution of. 



Dissolve 10 grammes of crystallized ammonic bichro- 

 mate in a litre of distilled water. 



4. Canada balsam*. 



A chloroform or turpentine solution of fairly fluid con- 

 sistency should be employed. It must be kept in a well- 

 stopped bottle with a wide neck. 



5. Carmine, Solution of. 



Carmine 2 grammes. 



Strong solution of ammonia 4 cub. cent. 



Distilled water 48 cub. cent. 



Dissolve the carmine in the ammonia and water ; leave 

 in an unstoppered bottle until nearly all smell of ammo- 

 nia has gone. Afterwards keep in a well- closed bottle. 

 Dilute a small quantity with fifteen or twenty times its 

 bulk of water, when required for use. 



6. Carmine, Borax, Solution of. 



Carmine I gramme. 



Borax 4 grammes. 



Distilled water 56 cub. cent. 



To this solution add twice its volume of absolute alcohol. 

 Filter. 



7. Chromic acid, Solution of. 



Dissolve 10 grammes of crystals of chromic acid in one 

 litre of water. This gives a i per cent, solution, from 



