THE PINK BOLLWOEM. 17 
that it had been disinfected; that it be allowed to proceed only to 
mills outside of the cotton belt; and that it be sent to southern cotton 
mills only after a period of storage of 18 months or more in northern 
localities. At the public hearing, and subsequently through con- 
ferences with members of the cotton trade and representatives of 
manufacturing associations whose assistance was very valuable to 
the department, it became evident that there were insuperable ob- 
stacles in the way of any of the plans mentioned. It therefore 
became necessary to make an exhaustive study of the possibility of 
destroying any infestation which might be found in the bales of 
lint. The use of cold was found to be impracticable. The use of 
heat was also impracticable on account of the time necessary to 
penetrate the highly compressed bales of Egyptian cotton and on 
account of the increased danger from fires when bales which had 
been heated were opened in the mills. 
About this time Mr. E. R. Sasscer, of the Federal Horticultural 
Board, and Dr. Lon A. Hawkins, of the Bureau of Plant Industry, 
had been conducting some experiments in the destruction of insects in 
various plant products by fumigation in a vacuum. It was found 
that the killing power of hydrocyanic-acid gas was increased enor- 
mously in vacuum and it thus became possible to reach certain 
classes of insects which heretofore had been uncontrollable. It there- 
fore seemed possible that the vacuum process might be utilized in 
the fumigation of bales of cotton without necessitating their open- 
ing. A small experimental plant was established by the board at 
Washington and a long and what turned out to be a most interesting 
series of experiments was begun by Mr. Sasscer. 
While this investigation was in progress an order regulating 
the entry of all imported lint cotton was promulgated by the 
Secretary of Agriculture April 27, 1915, effective July 1, 1915, 
and a domestic quarantine regulating the. movement of cotton lint 
from the Territory of Hawaii to the mainland was promulgated 
June 11, 1915, effective on and after July 1, 1915. Under this order 
and quarantine, tentative regulations were issued governing and re- 
stricting the entry of foreign cotton and also providing for the 
screening of all rooms or buildings in which foreign cotton was kept 
and the daily burning of all grades of mill waste in which seeds of 
such cotton might be found. A corps of inspectors was employed 
and frequent examinations were made at the mills where foreign cot- 
ton was used to insure the faithful following of regulations. In 
general sympathetic coooperation was obtained. This was especially 
noticeable in the case of southern mills, the owners and managers 
of which seemed to realize the danger of introducing the pink boll- 
