396 AGRICULTURAL REPORT. 
Davis, Hitchcock, Nourse, McCormick, and Knox. Aboutthe time Knox 
obtained his patent, Joshua Gibbs, of Canton, Ohio, selected a large 
piece of wood, and formed it as nearly as possible into the shape he 
considered a mold-board should be, attached to it a beam and handles, 
and with this rough implement commenced his labors in the field, stop- 
ping now and then to hew away with his adze that part of the mold- 
board which he found scoured most by the soil, until, by successive 
trials, he obtained a wooden mold-board all parts of which presented 
equal resistance to the soil in its forward movement. August 15, 1854, 
he obtained a patent for his mold-board, and to enable others to con- 
struct it he thus describes it in his specification: 
The working surface of the mold-board consists of about one-fourth of the interior sur- 
face of a hollow cylinder. If the plow is intended to turn a surtace six inches wide, a 
mold-board made from a cylinder with about a twelve-inch bore is desirable ; but if it 
is intended to turn a furrow twelve inches wide, the mold-board should be made from 
a cylinder with a bore of about twenty-four inches; as these plows have been found 
to work best when they turn a furrow about as wide as the radius of the bore of the 
cylinder from which the mold-board was made. It has been found from experience that 
these plows work best when the length of the mold-board is from one and a half to 
twice the diameter of the bore of the cylinder from which the mold-board is made. 
The advantages of this form of mold-board are also set forth in the 
specification as follows: 
1. The plow draws easier. 2. It raises the furrow from the point and share more gener- 
ally, naturally, and easily, turns and lays the furrow more uniform, smooth, and even, 
than any other mold-board, and leaves the trench wider in proportion to the width of 
the plow, and consequently the rear of the plow need not be set so wide as when @ 
different mold-board is used. 3. It breaks the sward or furrow far less than any other. 
4. The mold-board, being move arched, is stiffer and stronger than others of the same 
size and weight. ° 
He claims: : 
Making the working surface of the mold-board in the form of a section of a hollow 
cylinder; the center or axis of the cylinder being parallel or nearly parallel horizon- 
tally to the base of the moid-board, substantially as described. 
For the past few years no marked advantage has been gained in the 
form of the mold-board, although bundreds of patents have been ob- 
tained, and many applications rejected. During the past year inven- 
tion has been turned to a considerable extent to “plow attachments,” 
one of which is represented by Fig. 2, Plate 15. 
The object of this invention is to produce a device which shall cut 
asunder all the weeds or stalks that may come in contact with the 
colter, and it consists in an adjustable revolving hub having radiating 
arms or cutters upon it, which, as the plow is drawn forward, insert 
themselves into the ground, making the axle with the hubs and arms 
revolve, and as they revolve in contact with the adjustable colter of 
the plow, the weeds, &c., gathering in front of the colter, must be cut 
by the colter. A represents the plow-beam; B the long arm of the 
colter, pivoted to the plow-beam A at a, and has arm b projecting up- 
ward, and pivoted to Bata. This arm l passes through a screw staple 
f,in the beam a, by which means the arm B and colter B are adjusted 
to go deep or shallow as desired. C is a hub which revolves freely on 
its axis d, and has four or more radial arms or cutters c, secured by 
screw-bolts, and as the plow, with the inclined colter, moves forward, 
the cutters ¢ are brought successively in contact with, and pass along 
the edge of, the colter in such a manner that the weeds, &c., accuma- 
lating in front of the colter must be cut, leaving that part en the land 
to remain till the next succeeding furrow is made, and that part lying 
on the furrow slice being cut will be turned under by such furrow slice 
into the bottom of the furrow. The hub ©, with its arms or cutters ¢, 
