28 Of the Coulter. this ſurface points to the left of the fore end of the beam: but when the land fide of the: plough,‘and the line. of draught are in the ſame plane, the plough will go ſmoothly and ſteadily, without any effort of the ploughman. This conſideration leads us to attend a little to the form of the beam. The mortiſe, for receiving the coulter, muſt be in the middle of the thickneſs of the beam, in. order to, aive.the„graateſt ſtrength. The ſame may be ſaid of the mortiſe in the ſtilt for receiving the beam. The coulter muſt be ſet tothe left of the land ſide of the plough, near- Iy the thickneſs of its back, by which means the earth, which is puſhed a little to the right hand by the thickneß of the coulter, will be received on the edge

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