BACTERIAL INOCULATION 249 



serum. The syringe (Fig. 38) constructed entirely of 

 glass or one having an asbestos piston is most service- 

 able, as it permits of ready cleansing and sterilization 

 by boiling. When inoculations are given on a large 

 scale, requiring frequent sterilization, the oil method 

 of Wright is novel, convenient and effective. It con- 

 sists in heating a quantity of olive oil over a gas flame. 

 The oil will heat to 150° C. without boiling. This is 

 one and a half times the temperature of boiling water 

 and instantly sterilizes the syringe when drawn up and 

 forced out after inoculation. From the ampoule after 



Fig. 38. — All-glass hypodermic syringe. Desirable for bacterial inoculations because 

 of ease of cleansing and surety of sterilization. 



filing or breaking off its neck or from the small bottles, 

 • — in the case of the rubber-capped one by plunging 

 the needle through a drop or two of phenol, formalin 

 or alcohol placed on the rubber, — the desired dose of 

 bacterin is drawn up into the syringe. In the case of 

 some vials with rubber stoppers it is expedient to with- 

 draw partially the piston of the syringe before thrust- 

 ing it through the cork, then to push it home and as it 

 is slowly withdrawn again the desired quantity of bac- 

 terin readily follows the piston. If the skin is firmly 

 grasped and lifted between the finger and thumb and 



