XXIV 

 SUBSTITUTES FOR THE TRACTOR 



WITH the coming of the internal-combustion motor 

 interest in application of mechanical power to farm 

 work has broken out afresh in all directions. The 

 system of direct traction, wherein a self-propelling 

 prime mover draws behind it the plows, binders, or other working 

 devices, has, for the present at least, been accepted as standard 

 by the American trade and public. The direct traction motor, 

 which is built to resist the tremendous tug of a number of plows 

 at the drawbar, is also best adapted for pulling the other field 

 implements and machines, all of which have been developed for 

 transforming an animal's straight pull into linear, reciprocating, 

 or rotary working motion. 



By linear working motion we mean a straightforward move- 

 ment, such as we find in the plow or the harrow. The imple- 

 ment's peculiar shape is relied upon to produce the desired effect 

 upon the soil. Reciprocating motion is seen in the cutting 

 knife of the binder or mowing machine. The linear pull of 

 the horse is transformed first into rotary motion by the drive- 

 wheel, gears, etc., thence into reciprocating motion by a crank 

 disk and pitman. Rotary working motion of the simplest kind 

 is seen in the disk harrow, the cornstalk cutter, the alfalfa 

 renovator, and the stubble digger. Here the work is done by 

 wheels, which not only carry the weight of the frame, but are 

 of the shape required for the work in hand. More complex 

 rotary working parts are found in the cylinder type of hay 

 loader and hay rake, in the hay tedder and the manure 



