136 MECHANICS. 



connected as shown in fig. 144. The ditching plow, 

 exhibited in fig. 147, is similar in the construction of 

 Fig. 144. this part, and it 



has been fiaund 

 to work well 

 for sul>soiling, 

 particularly in 

 stony land. If 

 the subsoil hap- 



Brace-shank SubsoUer. pens tO be filled 



with roots, the interstices in these plows sometimes become 

 choked a difficulty, however, which rarely occurs. In 

 such cases it may be better to employ the plow represented 

 by fig. 141. 



New subsoil plows have been lately constructed at the 

 West, by which the operations of both plows are perform- 

 ed at once. A saving is thus made in the expense of the 

 implement and in the labor of one man. In one, known 

 as the Nichols' plow, a flat, triangular blade runs a few 

 inches below the common plow; in Wheatley's, a narrow 

 blade bent like the letter U beneath the j^low performs 

 the work. 



The benefit of subsoiling will last three or four years ; 

 but it is of great importance that land be well under- 

 drained, for if the earth becomes heavily soaked with wa- 

 ter, it settles down into one compact mass, and the advant- 

 ages of the operation are lost. 



THE PARING TLOW 



consists merely of a flat blade, which nins beneath the 

 surface, shaving off" the roots, but not moving the soil (fig. 

 145). A shield, shown in the cut, is placed beneath the 

 beam, to regulate the depth of the cutting blade. It is 

 used in cutting turf for burning, and for destroying this- 

 tles and other deep-rooted weeds. "When made light for 

 a single horse, it is sometimes used advantageously for 



