LIQUID MEDIA. QI 



by boiling with distilled water, after maceration for 

 several hours. The filtrate is received into sterile 

 flasks and sterilised in the usual way in the steam 

 steriliser. 



ARTIFICIAL FLUIDS. 



Pasteur's Fluid. This solution is prepared by 

 mixing the ingredients in the following propor- 

 tions : 



Distilled water , . . .100 



Pure cane sugar . . . .10 

 Ammonium tartrate i 



Ash of yeast .-. * . . . -075 



Cohn-Mayer Fluid. Mayer's modification of 

 the nourishing fluid employed by Cohn is as 

 follows : 



Distilled water .... 20 



Phosphate of potassium . . . 'i 



Sulphate of magnesium . . . "I 



Tribasic calcium phosphate . . *oi 



Ammonium tartrate . . . *2 



(F) METHODS OF STORING AND EMPLOYING LIQUID 



MEDIA; LISTER'S FLASKS, AITKEN'S TEST-TUBES, 

 STERNBERG'S BULBS, PASTEUR'S APPARATUS, 

 MIQUEL'S BULBS; DROP-CULTURES. 



Cultivations in liquid media can be carried on 

 in test-tubes, but it is more satisfactory to employ 



