490 APPENDIX. 



Use. As a fixing and 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. 



CORROSIVE SUBLIMATE, solution. 



Preparation. Saturate 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 warm or 

 cold. 



After use it should be washed out in alcohol, to which a 

 little tincture of iodine is added. 



CORROSIVE- ACETIC, mixture. 



Preparation. Take 90 vols, of concentrated sublimate solution 

 and add 10 vols, of glacial acetic acid. 



Use. An excellent fixative for general work. Wash out in 

 successive strengths of 50. 70. and 80 per cent, alcohol. 



FLEMMING'S SOLUTION. 



Preparation. Fifteen parts chromic acid (1 per cent), 4 parts 



osmic acid (2 per cent.), with or without 1 part glacial acetic 



acid. 

 Use. Good fixative and hardening reagent. Wash well in 



running water for 24 hours. Then place in alcohol, 



beginning with 30 per cent. 



MULLER'S FLUID. 



Preparation. 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 cells may be separated by teasing. 



OSMIC ACID (Os0 4 ), 2 per cent, solution. 



Preparation. Dissolve 1 grm. ' osmic acid ' crystals in 50 c.c. 

 distilled water. Keep in the dark. 



Use. For killing microscopic animals the vapour is a good 

 fixative. Before using the solution, it is to be diluted with 

 1-3 times its bulk of water. Avoid inhaling the vapour. 



