430 APPENDIX 



COEEOSIVE SUBLIMATE, solution. 



Prepa/ration.^S&iaxa,te water with mercuric chloride : 1 litre 



dissolves about 70 grms. 

 Use. — (1) As a hardening reagent it is used cold. 



(2) For killing small animals it may be used hot or cold. 



ABSOLUTE ALCOHOL. 



Use. — Hardening reagent, but most used for dehydrating speci- 

 mens before putting them into oil of cloves or turpentine. 



ALCOHOL (Spirit). 



It is used of the following strengths : 90 per cent., 70 per 

 cent., 50 per cent., 30 per cent. 



Prepa/ration. — 90 per cent, alcohol is the ordinary 'methy- 

 lated spirit.' The weaker solutions are obtained by 

 diluting it with water. 



Use. — (1) For preserving specimens ; not weaker than 70 per 

 cent. 



(2) Hardening reagent; 90 per cent. 



(3) For dissolving the intercellular substance of certain 

 tissues, so that the cells may be isolated by teasing ; 

 SO per cent. 



CnbOMIC ACID, 10 per cent, solution. 



Prepa/raiAon. — Dissolve 10 grms. chromic acid crystals in 

 100 CO. water. 



Use. — With or without addition of nitric acid for decalcifying 

 bone, etc. As a hardening reagent it must be reduced to 

 a 1 per cent, or '5 per cent, solution by addition of water 

 before use ; and osmic acid may be added to it. 



IIULLEB'S FLUID. 



Prepa/raUon. — Dissolve 25 grms. potassium bichromate and 

 10 grms. sodium sulphate in 1 litre water. 



Use. — Hardening reagent. It also dissolves intercellular sub- 

 stance, so that the oeUs may be separated by teasing. 



ACETIC ACID, 1 per cent, solution. 



Preparation. — Dissolve 10 c.c. glacial acetic acid in water : 



make up to 1 litre with water. 

 Use. — For clearing tissues, and especially for rendering nuclei 



more distinct. 



