110 BIOLOGY AND TECHNIQUE 



for insects as it is for rodents. The element of danger to human 

 life must be always considered in carrying out such fumigation, but 

 the writers referred to believe that there is no danger to men enter- 

 ing a place fumigated in this way 30 minutes or longer after the 

 apertures have been opened. Subsequent experience -in the fumiga- 

 tion of vessels has shown that longer periods of ventilation are 

 necessary, depending on the conditions of moisture and air currents. 

 In spite of rigorous precautions, loss of life has occasionally occurred 

 when cyanide is used as a routine procedure. For the fumigation 

 of the hold of a ship, Creel, Faget, and Wrightson 74 use an ordinary 

 wooden barrel, into the top of which is placed a large galvanized 

 iron funnel. The cyanide, in 5-gal. tins with top removed, may be 

 attached to the funnel and dumped into the sulphuric acid by means 

 of a rope attached to the tin, after the barrel has been lowered. 



74 Creel, Faget, and Wrightson, United States Public Health Keports, Vol. 30, 

 No. 39, Dec. 3, 1915. 



