124 ANTISEPTICS AND DISINFECTANTS 



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 apartment. 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 dilute 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 water 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 thick 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. 



Alcohol. Ninety-five percent and absolute alcohols are not 

 antiseptic for the anthrax spores, since they will live for many hours 

 in contact with absolute alcohol. In general it is unreliable. 

 Seventy percent alcohol is the most efficient strength. 



Zinc chloride in concentration is a powerful germicide. A 2 



