A HAND GRAIN THRASHER. 1 



By Lyman J. Briggs, Bio physicist in charge of Biophysical Investigations. 



The simple hand thrasher shown in the accompanying illustration 

 (fig. 1) has proved so useful in thrashing small quantities of grain in 

 water-requirement investigations that a description of it may be of 

 interest in connection with head-to-row experiments and similar inves- 

 tigations. As in other types of hand machines, the grain is thrashed 

 by passing it between a rotating rubber-covered cylinder and a sta- 

 tionary apron. The novel features include means for adjusting the 



Fig. 1.— A hand grain thrasher. 



tension of the apron against the cylinder and a provision for the 

 rapid cleaning of the machine. 



The frame of the machine is built of steel, so as to give an open 

 construction for convenience in cleaning, and is securely fastened t<> 

 its table. The cylinder is built up from disks of wood 2 inches thick, 

 glued together. The shaft is then forced into place and the cylinder 

 turned true on its shaft. This wooden cylinder is then covered with 

 a good quality of rubber matting, the corrugations being parallel 



i Issued Mar. 29, 1913. 



ICir. X19] 



23 



