126 



Report on Trials of Plows. 



best when the length of the mould-board is from once and a half 

 to twice the diameter of the bore of the cylinder from which the 

 mould-board is made, and the form of its exterior edges about the 

 same as represented in the drawing, the mould-board may b.e 

 fastened to the other parts of the plow as may be convenient or 

 desirable, taking into consideration the material from which it is 

 made. The share is fitted to the lower edge of the mould-board, 

 and its point is fitted to a recess in the heel of the coulter, C. 



J^iff. 72. 



"It has been found that when the top of the land side was 

 made parallel with the bottom, and a wooden standard fitted to 

 it, with a shoulder fitted against the top edge of the land side, 

 that the shoulder upon the wooden standard is soon worn oft' as 

 the wood wears away, so as to leave the plow defective and liable 

 to get loose and shackling. 



" To remedy this defect, and improve the plow in this respect. 

 I make the top of the land side, D, opposite to the wooden stand- 

 ard, E, at an angle about as represented in the drawing, that is, 

 liigher towards the forward end of the plow, so that the iron land 

 side shall protect the shoulder of the wooden standard, E, and 

 prevent it from being worn off, so as to preserve a shoulder upon 

 the standard, E, as long as there is any of the iron of the angle, 

 F, remains upon the land side to press against it, when the false 

 coulter, or bolt, G, is screwed up to hold the parts together." 

 Claim — " making the working surface of the mould-board in the 

 form of a hollow cylinder; the centre or axis of said cylinder 



