THE DESTRUCTION OF BACTERL* M31 



the subcultures as soon as made. The tubes may, however, be placed 

 in order in suitable racks without labeling. The subculture tubes 

 are incubated for 48 hours at 37 C. and those in which growth is 

 observed are recorded positive. 



DETERMINATION OF THE CARBOLIC-ACID COEFFICIENT 

 OF A DISINFECTANT. 



(ANDERSON AND McCLiNTic) 



NAME "A" 



TEMPERATURE OF MEDICATION 20 C. 



CULTURE USED B. TYPHOSUS 24-hr!, Extract Broth, Filtered 



PROPORTION OF CULTURE AND DISINFECTANT 0.1 c.c. +5 c.c. 



ORGANIC MATTER, NONE; KIND, None; AMOUNT, None. 



SUBCULTURE MEDIA Standard Extract Broth 



REACTION : +1.5 



QUANTITY IN EACH TUBE 10 c.c. 



To obtain the coefficient the weakest dilution of the unknown 

 antiseptic which kill in 2y 2 minutes is divided by the weakest 

 dilution of phenol which kills in the same time. The same is done 

 for the weakest strength that kills in 15 minutes and an average is 

 taken. The results of such a test are shown in the table on page 104. 



