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veil, by (nearis of a second plough following in the same furrow,and throwing the second furrow-slice on the top of the first.In this case, the first plough may go eight inches deep, andthe second four or five. Shallow ploughing* as four inchesdeep or less, ought always to be used when covering lime,which naturally tends to sink in the soil. When coveringdung, a substantial furrow ought to be given.

The great difficulty in ploughing is, to determine the widthand depth of the furrow-slice, which must vary according tothe object the farmer has in view, the nature of the precedingand succeeding crops, and the quality and depth of the soil.The general rules regarding this subject are, to give the fur-row for fallow or turnips as deep as possible, but after tur-nips are eaten on the ground, a very shallow furrow is to bepreferred. After dung, the fiirrow must be sufficient tocover it. After lime, it cannot be too shallow.

The depth of ploughing, as already observed, must, in agreat measure, be regulated by the soil to be-worked. Onthin soils, more especially on a rocky substratum, ploughingmust necessarily be shallow ; but where the soil is of a suffi-cient depth, it is material to give a substantial fiirrow at thecommencement of a rotation, and afterwards to vary thedepth, according to the different crops intended to be raised.If summer fallows are not ploughed deep enough, when theyreceive the first furrow, it is by some considered to be im-practicable, in a dry season, to go to a sufficient depth after-wards, though it is desirable not to go deeper, than is requi-red to clear the soil of every description of root weeds *.

In regard to the advantages of deep ploughing, {which is amost important branch of the Scotch system of husbandry),

* Others contend, that it is not impracticable, though certainly attended withdifficulty and hard labour; yet some people plough shallow at first, and after clean-ing the soil thus turned up of root weeds, go to the utmost depth they intendwith the nest furr, and clean the remainder,