OF THE HUMAN SUBJECT. 77 



is carried out as follows: The best culture medium is Lbffler's 

 blood serum, though ascitic or pleuritic, or even hydrocele fluid 

 answers sufficiently well ; the medium is solidified by heat in 

 test tubes placed on the slant to furnish a surface on which the 

 microbes may be sown. The serum slant may be inoculated by 

 means of the platinum ose ; this having been first sterilized in 

 the flame is drawn over the tonsil or pharynx (over the mem- 

 branous exudation if such is present) and is then rubbed over 

 the whole surface of the medium so as to distribute the organ- 

 isms present as widely as possible. Or the serum may be more 

 effectively inoculated by means of a small swab of cotton. 

 The swabs for this purpose are made by passing a strip of cotton 

 through an eye at the end of a piece of stout copper wire 

 around which the material is then twisted for a short distance 



c 



Fig. 6. A reduced figure of the swab, etc., described in the text. 



(Fig. 6). The opposite end of the wire is bent to afford a hold, 

 and a second piece of cotton is wrapped around near this as a plug 

 which closely fits the mouth of the test tube, into which the 

 swab is inserted. 



A set of such tubes may be sterilized by being heated for an 

 hour in the hot-air sterilizer at 150 0, and can be kept ready 

 for use. When about to be employed the swab is removed from 

 the tube and applied to the most promising area of the throat ; 

 it is then introduced into the culture tube and gently moved 

 over the surface of the serum The swab may then be destroyed 



