140 ANTISEPTICS AND DISINFECTANTS 



bacteria after twelve hours. It is best to keep the room closed 

 for twenty-four hours. It may be thrown into the room in many 

 ways; by generators which decompose the vapor of wood alcohol, 

 when they reach hot platinum sponges, salt, or hot copper; by 

 vaporizing a solution by means of heat; by adding permanganate 

 of potash to a solution of formaline; by spraying a concentrated 

 solution over bedding, floors, and walls, then closing the apart- 

 ment. It is very much more active in warm air than in cold, and 

 when the air is moist. It has been known to destroy anthrax 

 spores wrapped up in paper and placed under blankets. All of 

 the pathogenic bacteria are killed by it, the Staphylococcus 

 aureus and anthrax spores being more resistant than anything 

 else. It will not kill moulds unless highly concentrated. As di- 

 lute watery and alcoholic solutions decompose they should only 

 be used when freshly made. 



Sulphur Dioxide Gas. An old and rather unreliable form of 

 disinfectant. It does not kill anthrax spores very readily, as 

 it requires an exposure of twenty-four hours to a 40 percent vapor 

 in a room. It is generated by burning sulphur in a room tightly 

 closed, and it is much more efficient if weter is vaporized in 

 the room. It is not very penetrating, is poisonous to breathe, 

 speedily bleaches fabrics, and attacks metal objects. It is much 

 superior to formaline as an agent for the destruction of insects, 

 especially mosquitoes, also to kill rats infected with plague bacilli. 



Lime. Ordinary quick lime, or whitewash, is highly germicidal. 

 It is especially efficacious in disinfecting feces from typhoid cases. 

 Typhoid bacilli are killed after one hour's exposure to a 20 percent 

 mixture. 



Potassium permanganate in 3 percent solution is said by Koch 

 to kill anthrax spores in twenty-four hours. It is not so efficient 

 a germicidal agent as supposed. 



Turpentine and essential oils are efficient germicides in con- 

 centration. Common mustard rubbed in the hands is said to 

 make them sterile. 



