MACHINERY 



MACHINERY 



1945 



slips smoothly off witluml stickins. Tlio plow must, 

 theroforp, bo carefully jiolishctl and not allowed to rust. 

 If the face is of good hard metal, hard soil-grains cannot 



scratch it. 

 The plow 

 must also be 

 properly ad- 

 justed and 

 the share 

 and mold- 

 board joined 

 perfectly in 

 order to insure per- 

 fect scouring. 



The riding-plow 

 is more convenient 

 than the walking- 

 plow and generally 

 does better work, 

 Two general types, the frame 

 The frame plow (Fig. 2257) 



2257. Frame riding-plow. 



2258. Frameless riding-plow. 



particularly in dry soils, 

 and frameless, are made 

 has its wheels at^ 

 tached to a frame 

 which is connected 

 to the plow-beam 

 by "bails." This 

 arrangement per- 

 mits the lifting of 

 the plow within the 

 frame and the beam 

 may be "floated" 

 so that if the plow 

 strikes a rock or 

 other obstruction 

 the plow only is 

 raised and not the 

 frame and the oper- 

 ator. The frame- 

 less plow (Fig. 22.58) 

 has no special frame- 

 work and the wheels 

 are attached di- 

 rectly to the beam 

 by means of wheel brackets. 



In the riding-plow, the side and down- 

 ward pressure due to turning the furrow- 

 slice is carried by the wheels and not as 

 sliding friction, as in the walking-plow. It 

 will be noted that the furrow-wheels are 

 set at an angle better to carry the landside 

 pressure. The rear furrow-wheel is usu- 

 ally turned a little from the unplowed land 

 and in order to reduce the pressure on 

 the landside is set toward the unplowed 

 land 1 to 1 1^ inches beyond the landsific. 

 The front furrow-wheel is turned toward 

 or from the unplowed land, according to 

 the number and arrangement of the horses, 

 anfl serves a.s a sort of side-draft equalizer. 

 The plow is given the same suction as a walking-plow 

 and the landside heel is raised about ^•'2 inch from the 

 furrow-bottom. The point is set the same as for a 

 walking-plow. 



A sulky gang-plow is ong_having two or more plow- 

 bottoms, so that two or more furrows may be plowed at 

 one operation. Fig. 22.59 illustrates a sulky gang-plow. 

 A subsoiling attachment (Fig. 22.50) is sometimes 

 attached to one of the bottoms of a double gang-plow 

 so that alternate furrows may be .subsoiled. 



The disc-plow (P'ig. 226(J) is the result of an attempt 

 to reduce plowing draft due to sliding friction. In 

 ordinary soils it has been found to have no material 

 advantage over the moldboard-plow and the draft is in- 

 some cases greater. In sticky or very hard dry soils, 

 however, it usually has the advantage over the mold- 

 board-plow and operates witli less draft. 



The harrow. 



The harrow is perhaps second in importance to the 

 plow as a tillage implement. While the i)low breaks 

 the soil and pulverizes it in a general way, the harrow 

 does finer work by breaking up clods and pulverizing 

 the soil in detail. The original harrow was a tree limb 

 with most of the branches extending on one side. Other 

 early ty])es were a forked limb with spikes driven in each 

 arm and a rectangular-shaped frame having cross-bars 

 each containing several teeth. 



The main purposes of the harrow as a tillage tool 

 may be enumerated as follows: (1) To effect pulveriza- 

 tion and to secure a uniform soil-texture; (2) to destroy 

 young weeds; (3) to improve soil-aeration; (4) to smooth 

 the soil-surface; (.5) to check evaporation; (6) to pro- 

 pare a shallow seed-bed; (7) to cover seed; and (8) to 

 mix manure with the surface soil. 



Harrows may be groupctl under perhaps three dis- 

 tinct tjrpes, according to the work they accomplish, 

 as toothed- or smoothing harrows, disc-harrows, and 

 curved-knife, clod-crusher, or jjulverizer-harrows. 



The toothed-harrow is effective in pulverizing and 

 smoothing the surface soil of plowed ground. The fine 

 surface structure produced tends to prevent loss of 

 moisture by evaporation. Young weeds are also 

 destroyed at a tender age. A common type of toothed- 

 harrow is .shown in Fig. 2261. The toothed-harrow may 

 have either wood or steel tooth-bars, but the latter are 

 usually preferable. The number of teeth varies from 

 six to eight to a foot of width and these vary slightly 

 in size for light and heavy soils. The 

 lever enables the operator to incline the 

 teeth forward for penetration and pulver- 

 ization and backward for smoothing. 



A steel harrow riding-cart is now used 

 which may be attached so as to follow 

 the harrow. Its wheels are made to caster 

 to facilitate operations in turning. The 

 harrow cart is a desirable adjunct to the 

 harrow as it saves the hard labor of walk- 

 ing over plowed ground, and if properly 

 constructed with wide-tired wheels does 

 not cause an excessive increase in draft. 



The disc-harrow is an 

 implement of varied 

 utility. It is especially 

 adapted for rather deep 

 surface -cultivation. One 

 of its main uses is for pre- 

 paring a seed-bed in 

 plowed ground. It is like- 

 wise useful for preparing 

 stubble or sod for plow- 

 ing and for reducing sod 

 after plowing. It is also 

 useful as a general soil- 

 pulverizer, for covering 

 broadcasted seed in stub- 

 ble, and for destroying 

 weeds. In fact, many 

 of our foremost agri- 

 culturists state that 

 on an up-to-date farm 

 the disc-harrow is 

 indispensable. 



2259. Riding gang-plow. 



2260. Single disc-plow. 



