256 BACTERIA 



are thus suspended on fourteen consecutive days. The 

 first, second, and third are found to be of practically equal 

 virulence, but from the third to the fourteenth the virulence 

 proportionately decreases, and on the fifteenth day the cord 

 would be practically innocuous and non-virulent. When 

 treatment is to be commenced, obviously the weakest — that 

 is, the fourteenth day — cord is used to make the " vaccine,'* 

 and so on in steadily increasing doses (as regards virulence) 

 up to and including a third-day cord. The fourteenth-day 

 cord is therefore taken, and a small piece cut off and macer- 

 ated in 10 cc. of sterile broth, which are placed in a conical 

 glass and covered with two layers of thick filter-paper, the 

 glass with its covering having been previously sterilised by 

 dry heat. When the patient bitten by the rabid animal is 

 prepared, 3 cc. of this broth emulsion of spinal cord are in- 

 oculated by means of a hypodermic needle into the flanks 

 or abdominal wall. On the following day the patient returns 

 for an inoculation of a cord of the thirteenth day, and so on 

 until a rabid cord emulsion of the first three days has been 

 inoculated. As a matter of practice, the dosage depends 

 upon the three recognised classes of bites, viz. (i) bites 

 through clothing (least severe) ; (2) bites on the bare skin 

 of the hand; (3) bites upon the face or head, most severe 

 owing to the vascularity of these parts. An example of 

 each, which the writer was permitted to take in the Pasteur 

 Institute, may be here added to make quite clear the entire 

 practice. (See page 258.) 



It may be well to add the returns of inoculation made at 

 the Pasteur Institute, Rue Dutot, Paris, as above described. 

 They are as follows: 



-y. No. of Persons 



^^^^- inoculated. 



1886 2,671 



1887 1,770 



1888 1,622 



