Antiseptics and Disinfectants. 79 



tem, particularly if they are used continuously, even 

 though only in small quantities. Of the compounds 

 which may be used for this purpose, formalin, saly- 

 cilic and boracic acids and their derivatives are un- 

 doubtedly the least injurious, but their use is not 

 to be recommended under any circumstances. Some 

 attempts have been made to utilize the electric cur- 

 rent as a means of destroying germ life in milk ; 

 but they have so far proved ineffectual, and in- 

 stances are reported* where electrolysis of the milk 

 constituents occurred where a continuous current was 

 employed. Heat, then, is the only available agent 

 that can be used for the destruction of germs al- 

 ready present in the milk. This destruction of germs 

 in milk or any other fluid by means of heat is called 

 sterilization. In order to absolutely sterilize any sub- 

 stance, it is necessary that it should be subjected 

 to a heat of 212° to 240° F. for one hour on each 

 of three successive days. This will kill not only the 

 germs that are in active growing condition, but any 

 spores that may be present. A lower temperature, 

 175° to 212° F., will kill actively growing germs, but 

 even at this temperature chemical changes are set up 

 in the milk which give rise to flavors known as 

 boiled or cooked flavors, that are disagreeable to a 

 large number of people. In order to overcome the 

 bad effects of heating at such high temperatures 

 another process, known as pasteurization, is used. 

 Pasteurization. — The name is taken from Pasteur, 



*LTn4ustri^ Lajtier^, April 189Q, 



