30 THE APPr.I-: LF.AF IIOPPFK 



Before being used, crude petroleum was put into the pan, and the 

 canvas covering of the upper portion was also soaked with it. It was 

 then dragged along over the plants in the rows, the plants all passing 

 in at the middle of the front side of the hopper, and into the U-shaped 

 recess in the front of the pan, against the inner end of which they 

 struck with some force, jarring the insects off into the petroleum in 

 the pan. 



Tt seems probable, from our experience, that this hopper dozer 

 might be improved by reducing the abruptness of the corner where the 

 galvanized iron is turned u]:) at the inner end of the U-shaped recess, 

 thus making the h()])pL'rdozer less liable to break over or injure ]')lants. 



