138 MECHANICS. 



ing the turf beneath. In those of the best construction, 

 the depth is regulated by wheels, and the breadth of the 

 furrows by turning the cross-beatn more or less obliquely, 

 by means of a fixed contrivance for this purpose. The 

 gang plow is liable to become impeded or clogged by 

 stubble, coarse manure, or weeds, and has not come into 

 extensive use. 



DITCHHSTG PLOWS. 



In most localities where tile drains are made, two-thirds 

 of the labor of cutting is loosening the earth with the 

 pick, before shovehng it out. By means of the ditching 

 plow this laborious work is performed by horses. One 

 span, Avith a good plow made for this purpose, will loosen 

 the subsoil fast enough for eight or ten men shoveling, 

 and cutting about 100 rods 3 ft. deep in a day ; or an hour 



or two each day with 

 the plow will keep 

 two men at work. 

 If the subsoil is very 

 hard, this work 

 should be done early 

 in summer. The 

 implement is drawn 

 by two horses, at- 

 tached to the ends of a main whiffle-tree about seven feet 

 long, one walking on each side of the ditch. From one 

 to three times passing will loosen the subsoil five to eight 

 inches, which is then thrown out by narrow shovels, on 

 both sides, so that it may be easily returned after the tile 

 is laid, by means of a common plow drawn by the long 

 whiffle-tree before mentioned. 



There are several modifications of tlie ditching plow, all 

 accomplishing the same end. The adjustable ditching 

 plow, (6g. 147,) admits of so great a change in the lieight 



Fig. 14T. 



Adjustable Bitching Plow. 



