APPBRENDIX.

IMPROVEMENT OF THE DRILL PLOUGH.

| TE firft expefiment I tried to improve this valuable machine was | that mentioned in Sec. XII. 5. of this work, by enlarging the axis | of Mr. Tull’s feed-box into a wheel of fixteen inches diameter, with excavations in the rim to raife portions of the: corn.above the furface of that in the feed-box. But I found to my furprife the friction of the corn to be fo much greater than expected, when fix fuch large wheels were immerfed in it, that an additional hopper became ne- ceffary to deliver the feed flowly into the feed-box, as in Mr. Cook’s drill plough; which, as it would add much to the intricacy and ex- pence of the machinery, and to the inaccuracy of the quantity of feed delivéred, occafioned me to relinquifh that idea, and after many de- figas and many experiments to conftruét the following machine, which E believe to be more fimple, and confequently lefs expenfive to conftruét, and lefs liable to be out of order, and to deliver the feeds of all kinds with greater accuracy than any drill plough at prefent in ufe; and that it poñfefles every other advantage that they can boaff.. The fcale of the three following plates is half an inch to ten inches.

Confiruétion of the Carriage Part.

to the center of the axle-tree by a fimple univerfal joint at x, whence,

14

| Plate X. Fig, 1. a a, are the fhafts for the horfe, which are fixed: |

4