140 FARM MECHANICS 



All plows should have a leather pocket on the side of 

 the beam to carry a file. A 12-inch bastard file with a 

 good handle is the most satisfactory implement for 

 sharpening the cutting edges of a plow in the fields. A 

 good deal depends on the character of the soil and its 

 condition of dryness, but generally speaking, it p^ys to 

 do a little filing after plowing a half mile of furrow. 

 If the horses are doing their duty, a little rest at the 

 end of the half mile is well earned. The plowman can 

 put in the time to advantage with the file and the next 

 half mile will go along merrily in consequence. No 

 farmer would continue to chop wood all day without 

 whetting his axe, but, unfortunately, plowmen often 

 work from morning till night without any attempt to 

 keep the cutting edges of their plows in good working 

 order. 



Riding Plow. The riding plow in lifting and turn- 

 ing the furrow slice depends a good deal on the wheels. 

 The action of the plow is that of a wedge with the 

 power pushing the point, the share and the moldboard 

 between the furrow slices and the land side and the 

 furrow bottom. There is the same friction between the 

 moldboard and the furrow slice as in the case of the 

 walking plow, but the wheels are intended to mate- 

 rially reduce the pressure on the furrow bottom and 

 against the land side. Plow wheels are intended to re- 

 lieve the draft in this respect because wheels roll much 

 easier than the plow bottom can slide with the weight 

 of the work on top. The track made in the bottom of 

 the furrow with the walking plow shows plainly the 

 heavy pressure of the furrow slice on the moldboard by 

 the mark of the slip. To appreciate the weight the 

 slip carries, an interesting experiment may be per- 

 formed by loading the walking plow with weights suf- 



