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MOSQUITO ERADICATION 

 SOME TYPICAL DITCHING MACHINES 



Implement A. — This device 1 consists of a cutting knife, which 

 loosens the earth, and a bucket, which removes it. Two men 

 and a team are required to operate this machine. The cutting 

 knife is mounted on a steel frame; trimmers for widening the 

 ditch are bolted to the end of it. The bucket, which holds 

 about 5 cubic feet of earth, is hinged to the cutter frame by steel 



Fig. 78. — Implement A. (After U. S. Bureau of Public Roads.) 



straps. The lower end of a wooden handle is attached to a loop 

 near the bottom of the bucket; a hook on it engages the top of the 

 bucket between guides that keep the bucket from tipping while 

 the handle is straight. The depth of each cutting is controlled 

 by an adjustable shoe in front of the cutting knife. The bucket, 

 when full, slides out of the ditch, the handle is lifted to disengage 

 the hook and the bucket falls on its side. 



Implement B. — This implement consists essentially of a rever- 

 sible cutting blade attached to a steel landside at an acute angle. 

 The cutting blade not only loosens the earth, but also throws it up 

 on the side of the ditch. The device may be reversed to cut on 



1 Based largely on Farmer's Bulletin No. 698, U. S. Department of Agri- 

 culture, 1915, by D. L. Yarnell,.' 



