20 WOUND TREATMENT 



there was no growth, in two and one-half minutes; in 

 the 1 to 90, however, there was, showing the effect of 

 concentration. The lower table shows the effect of or- 

 ganic matter. For example, it took the 1 to 90 dilution 

 five minutes to kill against two and one-half minutes 

 without organic matter, or just twice as long. The 1 to 

 100 dilution failed to kill in two and one-half minutes 

 but was bactericidal in fifteen minutes, showing the 

 effect of exposure. 



Now the question arises as to what practical value 

 such tables as these have. There are upon the market 

 innumerable kinds of disinfectants put up by different 

 (iommercial houses at greatly varying prices, based, not 

 upon their efficiency as germ killers, but upon the per- 

 centage of profit the manufacturer thinks he ought to 

 get. For example, mixtures containing varying 

 amounts of creolin are upOn the market. All have 

 the property of forming a white emulsion with water 

 and in addition a more or less aromatic odor. The idea 

 seems to have gained precedence that odor and disinfect- 

 ing properties go hand in hand. The more penetrating 

 the odor and the more milky the solution, the better the 

 antiseptic, seems to be the belief. There are prepara- 

 tions on the market possessing both the latter qualities 

 to a superlative degree but having little action other 

 than imparting a pronounced odor to your medicine case 

 and clothing. The only true criterion of the value of 

 any given preparation as a germ killer is a bacteriological 

 determination. Every practicing veterinarian should in- 

 sist upon knowing the phenol coefficient of the antiseptic 

 purchased. The time is coming when all commercial con- 

 cerns will place the coefficient upon their labels, as some 

 houses are already doing. 



When the phenol coefficient and price per gallon of ^' 

 number of disinfectants are known, it is possible to' cal- 



