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BULLETIN 379, U.S. DEPARTMENT OF AGRICULTURE. 
The results of the investigation indicate that the wheat crop 
contained a large percentage of smut and that the explosions and 
fires in many cases were due to the formation of an explosive mix- 
ture of smut dust and air and the ignition of this mixture by static 
electricity during the threshing operations. This report briefly 
summarizes the results of the field work relative to the causes of 
ignition and describes the various preventive devices developed as a 
result of the investigation. 
PLAN OF INVESTIGATION. 
ORGANIZATION. 
The field work was conducted under a cooperative arrangement 
between the Bureau of Chemistry, where the general study of grain- 
dust explosions is being carried on, and the Office of Public Roads 
and Rural Engineering. Investigators were assigned to the various 
parts of the territory affected and a central office was opened in the 
Federal building at Spokane, Wash. J. E. Young, assistant agri- 
cultural engineer, conducted field investigations in thes vicinity of 
Walla Walla and Rosalia, Wash., and J. C. Woodson, assistant agri- 
cultural engineer, in the territory adjacent to Moscow, Idaho. H. H. 
Brown, assistant chemist, was assigned to investigations in the 
vicinity of Colfax, Wash. The organization and direction of the 
field work and the conduct of the investigation were in charge of 
David J. Price, engineer, of the Bureau of Chemistry, and E. B. Mc- 
Cormick, mechanical engineer, of the Office of Public Roads and 
Rural Engineering. 
COOPERATION WITH THE UNIVERSITY OF IDAHO. 
The investigations in northern Idaho were conducted in coopera- 
tion with the University of Idaho at Moscow, represented by Prof. 
N. S. Robb, of the Department of Farm Crops. Office room, labora- 
tories, and electrical apparatus were placed at the disposal of the 
investigators and experimental work was conducted in conjunction ~ 
with Prof. Angell, of the Department of Physics. The staff was 
much interested in the explosion problem in its territory and ren- 
dered valuable assistance during the conduct of the investigations. 
CONFERENCES WITH THE STATE COLLEGE OF WASHINGTON. 
Conferences were held at the beginning of the investigations with 
Dr: Iva D. Cardiff, director of the experiment station, State College 
of Washington, Pullman, Wash., and members of the staff. This 
problem had been studied by the station staff in 1914 and the results 
published in bulletin form.t During the conduct of the field work 
1 Washington Station Bulletin No. 117, Nov. 3, 1914. Report on Fires Occurring in 
Threshing Separators in Eastern Washington during the Summer of 1914. 
