208 GENERAL THERAPEUTICS FOR VETERINARIANS 



boilers carrying 8 atmospheres pressure (Kramell, Zeitschr. f. 

 Vet., 1901). On the other hand, milk cans and other small vessels 

 are surely disinfected with live steam under moderate pressure 

 (Junack, Monatshefte f. prakt. Tierheilk., 1904). The addition 

 of a slight quantity of a chemical disinfectant increases the effec- 

 tiveness of steam considerably; hides and leather articles (saddles) 

 which will only bear steam at 70° C. are disinfected in a relatively 

 short time by steam at 70° C. containing 1 to 2 per cent, of for- 

 maldehyde, even anthrax spores being destroyed in 5 minutes 

 (von Esmarch, Hygien. Rundschau, 12 Bd.). 



Cold cannot be used for disinfection. Very low temperatures 

 (—100° C.) do not destroy anthrax spores. Even the bacteria of 

 fowl cholera, which are rather easily destroyed, resist a tempera- 

 ture of -4°C. 



Mechanical Disinfectants. — 1. Burial is a very important 

 method of disposing of infected carcasses, cadaver parts, manure, 

 etc. (see the regulations for anthrax, rabies, glanders and lung 

 plague). Bacteriological investigations have shown that the 

 earth is free from bacteria at a depth of 5 feet, provided the 

 excavation is not made in the neighborhood of houses, stables, 

 manure pits, wells, etc., and does not reach the ground water. 

 Most of the pathogenic bacteria, except anthrax spores and tuber- 

 cle bacilli, die very soon in buried cadavers. Anthrax spores, 

 however, retain their virulence many years and tubercle bacilli 

 for several months (cholera and typhoid fever bacilli in human 

 bodies die in 2 to 3 weeks after burial). Investigations have shown 

 that the earth of cemeteries contains no more bacteria than the earth 

 of cultivated fields at an equal depth. On accoimt of the possibility 

 of buried spores being disseminated (earth worms, moles) , it is recom- 

 mended that anthrax carcasses be buried in cemented pits. 



2. Drying in the air has a very slight disinfectant action. An- 

 thrax spores retain their virulence in dry places for years, and most of 

 the more readily destroyed bacteria die only after several weeks. 



3. Light assists the disinfectant action of the antiseptics. 

 Spores appear to be more susceptible to light than the bacilli. 

 Anthrax spores are killed by sunlight m 5 hours, while the bacilli 



