EFFICACY OF DISINFECTANTS 51 



mouth disease. Repeated instances have been reported 

 where foot-and-mouth disease has been arrested, after a 

 portion of the herd has been attacked, by washing twice a 

 week the walls, floors, doors, and other woodwork of the 

 infected premises with carbolic acid, confining the animals 

 for several weeks to their sheds or boxes, and keeping them 

 surrounded by an atmosphere abounding in the tar^acids. 

 By similar disinfection, the progress of influenza and of 

 strangles in large studs has frequently been arrested. 

 Nocard has shown that when a cow aborts, whether from 

 accidental cause, or from virus introduced from subjects 

 which have previously aborted, further cases of the mishap 

 may be prevented by corrosive sublimate injections into the 

 vagina, washing the external organs with a, similar solution, 

 and disinfecting and burying or burning the aborted calf 

 and membranes. Incalvers standing with those aborting 

 should have the external organs and tail washed daily with 

 an antiseptic solution. 



Burning is the only absolutely safe method of destroying 

 the bodies of anthrax subjects, from which removal of the 

 hides is dangerous to persons employed or, it may be, to 

 other animals. Cattle plague subjects should be either 

 burned or deeply buried ; while for the diseased organs of 

 tuberculous patients the furnace is the only safe tomb. 



A high temperature, as already indicated, destroys infec- 

 tive particles. Koch, as above stated, found that the bacilli 

 of anthrax and swine fever, even when bearing spores, were 

 deprived of pathogenic power when exposed for four hours 

 to a temperature of 216 to 220 Fahr. ; while exposure for 

 five minutes to boiling water, or, better still, to steam heat, 

 is equally effective. The power of steam depends (1) on 

 its latent heat ; (2) on its moistening ; (3) on its condensing ; 

 (4) on its penetrating. It is most effective when employed 

 under pressure, and when its entrance into the chamber is 

 occasionally interrupted, so that cold air in the interstices 

 of bulky and non-conducting bodies may be displaced. 

 Russell, Glasgow, exposed all infected washable articles, for 

 three-quarters of an hour in a chamber, to steam heat, along 

 with soap and soda, and found that this treatment destroyed 

 bacilli of anthrax and swine fever, tuberculous pus, and also 



