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@NLTHE BTOUGH ii,

the lower edge of the wedge, continued for- ward to the point of the coulter*.‘Theufe of itis to cut out, and raife up the under furface; while the coulter performs a like operation on the fide. For this purpofe, it is generally made up of two different forms, fuited to the two different ftates of a hard or a loofe foil. If the foilis of the firft kind, the fhare is made tapering in fuch amanner,° that its point pafles nearly under the middle of the earth of the furrow; and confequent- ly deviates a little from the plane of the ieft fide of the plough. The point is made ta- pering, becaufe by this form it penetrates more eafily; and as the foil has great cohefi- on, by pafling under the middle of the earth of the furrow, it raifes up the whole.

The other form of this part of the plough is calculated for the loofe kind of foil, which has fo little cohefion, that it cannot be moved by penetrating below any particu- lar part of it, but almoft the whole of it muft be cut or fcooped out, before it can be raifed."To produce this effet, the point

. C of

* See fig. 6,