DISINFECTANTS. ANTISEPTICS 203 



etc., in infectious outbreaks; also, for the destruction of infectious 

 material difficult to destroy, especially as a cheap disinfectant for 

 anthrax spores and for the disinfection of urine. According to 

 Hansen (Monatshefte fiir prak. Tierheilkunde, 1912) the addition 

 of 0.2 per cent, of calcium chloride to liquid manure is a certain 

 and cheap disinfectant and is not harmful to vegetation and 

 does not destroy the fertilizing value. Chloride of lime is uncer- 

 tain against glanders and tuberculosis. A 1 per cent, solution 

 kills the bacteria of fowl cholera, swine erysipelas and hog cholera 

 and the bacilli of anthrax in one minute. Freund recommends the 

 use of a 5 per cent, filtered solution of chloride of lime for the disin- 

 fection of railroad cars; the process is very complicated (spraying 

 with a pumping apparatus under l}^ atmospheres pressure). 

 The formerly much used chlorine gas, in the presence of sufficient 

 moist air and in strong concentration (1 per cent, by volume), 

 will destroy all air-dried microorganisms within 24 hours, but 

 for practical disinfection it is of no value because the necessary 

 concentration is difficult to obtain and is very costly. The proc- 

 ess of chlorine disinfection is also very complicated and dangerous. 

 The same applies to bromine. 



Lyes. The antiseptic effect of the lyes was formerly over- 

 valued; their disinfection power is about equal to lime. Soda lye, 

 potash lye, soda and potash are in general of the same value. 

 Ammonia, on the other hand, is three to five times weaker. Con- 

 centrated solutions of these substances kill the bacteria of fowl 

 cholera and swine erysipelas and glanders and anthrax bacilli. 

 Anthrax spores and tubercle bacilli, on the other hand, remain 

 intact. An objection is the caustic action of solutions of the re- 

 quired concentration. Boiling hot soda solution possesses a very 

 high disinfection power. 



Soaps. The disinfectant value of soaps depends upon their 

 alkali content; the ordinary soft soap is therefore the most power- 

 ful. The action is increased by using boiling-hot soap water. 

 The latter kills the more readily destroyed infectious agents and 

 at the same time has a cleansing effect which assists the action of 

 the stronger antiseptics. A 10 per cent, solution of the ordinary 



