4 BULLETIN" 725, U. S. DEPARTMENT OF AGRICULTURE. 
of damaged grain, such as weather stained, heat damaged, bin burned, 
and ground damaged, was carefully noted. This same line of experi- 
mentation was carried on at several representative points in order to 
Fig. 2.— A grain bleaching apparatus with square tower. This type is in very common use 
throughout the Middle West. 
get the benefit of varying conditions. Acknowledgment of apprecia- 
tion is made for the assistance and cooperation given by the owners 
and operators of the elevators where experiments were conducted. 
