418 APPENDIX 



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 ceUs may be separated by teasing. 



CORROSIVE SUBLIMATE, solution. 



Preparation. Saturate water with mercuric chloride : 1 litre 



dissolves about 70 grms. 

 jjse.(T) As a hardening reagent it is used cold. 



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



PICRIC ACID, saturated solution. 



Preparation. Saturate water with picric acid, by shaking it 

 up with the crystals. Allow to stand : decant before use. 

 Use. Hardening reagent. 



PICRIC ACID, Kleinenberg's solution. 



Preparation. To 250 c.c. saturated solution of picric acid add 

 5 c.c. strong sulphuric acid : filter : make up to 1 litre with 

 water. 

 Use. Hardening and decalcifying reagent. 



ABSOLUTE ALCOHOL. 



Use. Hardening reagent, but most used for dehydrating a 

 specimen before putting it 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. 



Preparation. 90 per cent, alcohol is the ordinary ' methylated 

 spirit.' The weaker solutions are obtained by diluting it 

 with water. The specific gravity of each is as follows : 

 90 per cent. -833 ; 70 per cent. -889 ; 50 per cent. -933 ; 

 30 per cent. -965. 



U S6t (i) 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 ; 30 per cent. 



