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. E. 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 begim 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- 



