24 Of the Coulter.

the plough is more than ſufficientiy cleared, the upper part is not cleared: at all Accordingly, it may be oblſer- ved, that in ploughs- of this conſtruction, the upper part of the plateing on the land ſide is more worn away than the lower, although it moves in looſer earth. Ec is ſtrongly preſſed to: the firm land, while the parts near the ſole do not

touch it, or touch it after the upper

parts have been bruiſed together.

All theſe circumſtances conſidered to- gether, ſhow that a plough of this con- ſtrudion is in a ſtate of continual twiſt- ing, by the very unequal preſſure of its different partsto the land. This muſt be varied by changing the poſition of the coulter, ſo as to point its lower end more or leſs to the land; whereas, by

making