DUST EXPLOSIONS IF GRAIN" SEPARATORS. 3 



various x^hases of the problem were considered with the State College 

 staff. 



CONDUCT OP INVESTIGATIONS. 



Although investigations by the Department of Agriculture were 

 not conducted in the field during the 1914 threshing season, samples 

 of wheat smut dust from the Pacific Northwest were obtained at the 

 close of the season. Experiments at that time indicated that the 

 material was highly inflammable and might be associated with the 

 frequent fires and explosions in grain separators. 



The entire season extending from the first week in July to the 

 middle of September, 1915, was spent in field work in the territory. 

 Effort was made to visit the scene of each explosion or fire as soon 

 as possible after it had taken place and obtain all the available in- 

 formation pertaining to the occurrence. Arrangements previously 

 had been made so that prompt reports could be received at the Spo- 

 kane office, through various channels, and also by the men in the 

 field, so that no time would be lost in reaching the scene of the 

 explosion. In nearly 150 cases the investigator was on the ground 

 either immediately or within a few hours after the occurrence. In 

 many instances the explosions were so sudden and violent that the 

 crew could give very little information, but it was possible in the 

 majority of cases to make valuable deductions. A large percentage 

 of the thresher owners would not advance an opinion, but many of 

 them believed that matches or explosives had been placed in the 

 bundles. In many cases, however, this was mere conjecture and not 

 supported by evidence. 



CLASSIFICATION OF EXPLOSIONS. 



TERRITORY AFFECTED. 



The largest number of the 166 explosions reported occurred in the 

 counties of Wliitman and Spokane in eastern Washington, and the 

 counties of Latah, Lewis, Kootenai, and Nez Perce, in northern 

 Idaho. Eighty-three per cent of the total number of explosions and 

 fires reported occurred in this district. Of these 70 per cent occurred 

 in Washington and 13 per cent in Idaho. About 11 per cent of the 

 total number reported occurred in the Big Bend section in the Co- 

 lumbia River Valley in Washington, comprising the counties of 

 Adams, Lincoln, Grant, and Douglas. The remaining explosions 

 occurred in Walla Walla, Garfield, Yaldma, and Klickitat Counties. 

 Th© field investigations, however, generally were confined to the 

 Palouse country in eastern Washington and the northern Idaho ter- 

 ritory, t 



FREQUENCY OF EXPLOSIONS. 



The explosions began with the opening of the season in the Big 

 Bend country about the middle of July and continued until the 



