114 PATHOGENIC BACTERIA. 



Boracic acid . . . 

 Chloral hydrate . 

 Ferrous sulphate 

 Calcium chlorid . 

 Creosote . . . 

 Carbolic acid . . 

 Alcohol . 



143- 



107. 



901 : 200, Sternberg. 



25- 



20. 



20 : : i : 50. 

 10. 



Ether. Pure ether will not kill anthrax spores immersed 

 in it for eight days. 



The value of antiseptics, like that of disinfectants, is 

 always relative, the destructive as well as the inhibitory 

 power of the solution varying with the micro-organism 

 upon which it acts. The following table, from Boer, 

 will illustrate this : 



Methyl Violet (Pyoktaniri). 



Restrains. Kills. 



Anthrax bacillus i : 70,000 : 5000 



Diphtheria i : 10,000 : 2000 



Glanders i : 2500 : 150 



Typhoid i : 2500 : 150 



Cholera spirillum i : 30,000 : 1000 



Large numbers of both strongly and feebly antiseptic 

 substances have purposely been omitted from the above 

 lists, compiled from Sternberg and Micquel, as either in- 

 appropriate for ordinary use or as having been replaced 

 by better agents. 



The newest, and one of the best germicides for all pur- 

 poses is formaldehyde. Its use as a vapor for the sterili- 

 zation of infected rooms was first suggested by Trillat in 

 1895, but it did not make much stir in the medical world 

 until a year or more had passed and a 40 per cent, solu- 

 tion of the gas, under the name of " Formalin," had 

 been placed upon the market. The original method con- 

 sisted of the evolution of the gas from methyl alcohol by 

 volatilizing it in a steam apparatus, and passing the vapor 

 over a heated metal plate. At present the original auto- 

 clave has been replaced by the apparatus shown in Fig. 

 19, in which a solution of formochloral is volatilized by 

 heating under a pressure of three atmospheres. 



