History of tub Plow. 83 



the hooked part of the cutter, by which it may be extended at 

 pleasure Avhen the wearing of the cutter requires it. 



"The cutter is a plate of steeled iron, formed to the shape of 

 the plow in front and of a thickness so as to fill up the sunken 

 part l)efore described ; the under side of the upper part of the 

 cutter extends in a narrow form having a hook at the end, which 

 bends downwards and catches in the indents before mentioned; 

 when the last mentioned plate or cutter is in its place it causes the 

 surface of the land side to be flush and even. 



" Over the above described plates is placed another plate which 

 may be called the shelter plate, as it receives all the wear of the 

 land side; it extends the whole length of the plow, and covers 

 the under structure; the front part partakes of the shape of the 

 cutter and recedes a little from it; it is fastened either by screws 

 or bolts, which make the whole land side firm and secure. 



"The plate of the under side of the plow, which is cast with 

 the first plate of the land side, has on its upper surface an 

 indented groove and projects in front of the plow, and forms 

 what is called a nose; this bar, as it wears in plowing, may be 

 extended and turned at pleasure. On the right hand side of the 

 above mentioned groove there is a rising ratchet or toothed edge, 

 the indents of which prevent the under cutter from shifting its 

 situation when in the act of plowing. 



"The under cutter is formed of a proper shaps to suit the 

 under part of the plow, and is made either of wrought iron, 

 steeled, or entirely of iron ; the inner side is bent downwards for 

 the purpose of catching in the ratchets or teeth before mentioned, 

 when wanted to be brought forward, where it wears in plowing. 

 Towards the inner side of said cutter there is a long perfora- 

 tion for the purpose of admitting through it the shapes rising 

 from the cast plate, which fastens the cutter by a key. 



"The mould-board is a separate piece, and made of cast iron, 

 having proper staples or bolts in their proper situation for the 

 purpose of fixing it by keys or otherwise ; or it may be fixed by 

 screws. 



"This new construction of a plow may be adapted to any plow 

 already in use, and the cutters may be made either of steel, 

 wrought iron or cast iron." 



What is called the "under plate," in the specification, is a sort 

 of shelf extending across the fore part of the plow from the land 

 side plate to the mould-board ; it is about one and a half inches 



