346 EXPERIMENTAL INOCULATION OF ANIMALS 



15. Razor. 



1 6. Small pot of warm water. 



17. Liquid soap. Liquid soap is prepared as follows: Meas- 

 ure out 100 grammes of soft soap and add to 500 c.c. of 2 per cent, 

 lysol solution in a large glass beaker; dissolve by heating in a water- 

 bath at about 90 C. Bottle and label "Liquid Soap." 



1 8. In place of the liquid soap and razor it is sometimes con- 

 venient to use a Depilatory powder. 



Barium sulphide i part 



Rice starch 3 parts 



Dust the powder thickly over the aiea to be denuded of hair, 

 spi inkle with water and mix into a thin paste in situ; allow the 

 paste to act for three minutes, then scrape off with a bone spatula 

 the hair comes away with the paste and leaves a perfectly bare 

 patch. This process is preferably carried out, the day previous to 

 the operation. 



Material Utilised for Inoculation. The material in- 

 oculated may be either 



1. Cultures of bacteria grown in fluid media, or on 

 solid media. 



2. Metabolic products of bacterial activity e. g., 

 toxins in solution. 



3. Pathological products (fluid secretions and excre- 

 tions, solid tissues) . 



The Preparation of the Inoculum. 

 (a) Cultivations in Fluid Media. 



1. Flame the plug of the culture tube. 



2. Remove the plug and flame the mouth of the 

 tube. 



3. Slightly raise the lid of a sterile capsule, insert 

 the mouth of the culture tube into the aperture and 

 pour some of the cultivation into the capsule. 



4. Remove the mouth of the culture tube from the 

 capsule, replace the lid of the latter, flame the mouth 

 of the tube, and replug. 



5. Remove the syringe from the steriliser, squirt 

 out the water from its interior, and allow to cool. 



6. Raise the lid of the capsule sufficiently to admit 

 the needle of the syringe and draw the required amount 

 of the cultivation into the barrel of the syringe. 



