THE PRACTICE OF DISINFECTION 169 



DISINFESTATION 



The important part played by lice in the transmission of 

 disease has been demonstrated anew by the recent war, 

 and delousing, or "disinfestation " as it is called, has ac- 

 cordingly had considerable attention. In practice it has 

 been found that one of the most reliable means of de- 

 stroying lice in clothing is by the application of dry heat 

 or steam. Immersion of the garments in gasoline is also 

 highly effective and may often be more convenient. 

 Where there is a danger of fire, tetrachlorethane may be 

 used, as this is not inflammable. 



. To keep lice away the application to the body of a 

 grease containing naphthalene, coumarfn, heliotropin, or 

 certain other odorous substances has been recommended. 

 The effect of this wears off as the grease is absorbed by the 

 underclothing ; nevertheless the treatment is of service. 



So far as head lice are concerned, the application of 

 crude petroleum at night, the head being then bound in a 

 towel, followed by a thorough washing and combing in 

 the morning, will usually suffice to effect disinfestation. 



In the picture on the opposite page is shown the appli- 

 cation of poisonous gases to railway coach disinfestation. 



