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bine, that no animal above the size of a cat could penetrate; especially when it is of such a depth as I have recommended.

The first hint I got for a fence of this kind , was from a small thicket of brush-wood that I had planted for ornament, pretty much in the manner above described ; which, in a short time, became so much interwoven with the sweet briar, that it was impossible to find any access into it.

But, as all kinds of trees and shrubs, if planted very close upon one another, become naked at the root when they arrive at any considerable size, care should be taken to prevent it from ever coming to that state, bycutting it down whenever it is in danger of being open at the root.

And, as it would be improper ever to leave the field entirely defenceless, it is a, great advantage to have the belt as broad as it conveniently may be, so that the pne half of if may be a sufficient fence; by which means, we will have it in our power to cut down the inside and the outside of this belt alternately, so as still to keep the thicket young, and never to want, at any time, a sufficient fence* The brush-wood that this would afford at each cutting, would, in almost every situation, yield such a revenue as might do much more than indemnify the proprietor for the rent of the ground that was occupied by the fence. And, if the field was in such a situation as required shelter, some trees might be allowed to grow to their full size about the middle, without any inconvenience, if the belt were of a sufficient breadth.


§ xxvni.

Of securing the Banks of Rivers, so as iS prevent the Earth from being wa/hed aivay by the Violence of the Stream.

There is yet another species df fencing, as useful as any of these already mentioned* 'which is in general much less understood* and more difficult td execute properly, that deserves here to be taken notice of j viz. the method of securing the banks of rivers from being washed away by the violence of the stream, and of preventing the damages that may otherwise be occasioned by the swelling of the waters.

It frequently happens that, when a river runs in a bed of rich vegetable mold, the least accident that may chance to divert the 1 stream stream towards any particular part of the bank, causes it to sweep away large tracts of sine ground, to the very great detriment of the proprietor, as well as the pubiic; as this fine mold is usually carried to the sea, and the place that the water leaves to occupy the new bed that it thus forms for itself, is generally of a much worse quality, consisting chiefly of stones, sand, and gravel.

In some cases* where the whole force of the current is quite close to the bank, and the materials necessary for fencing it are not to be found* it may perhaps be impossible* or very difficult, totally to prevent this evil; but, for the most part, it admits of a cure that can be obtained at a pretty moderate expence.

If you carefully observe the banks of rivers, you will readily remark, that these ravages are always most considerable at those places where the bank rises perpendicularly to a pretty considerable height above the Q_ ordiordinary surface of the water, and never at those places where the banks shelve down gradually towards the water's edge. For, when the river is swelled to a great height by rains, and runs with a force and rapidity greater than usual, it strikes violently against these perpendicular banks that directly oppose its course ; and, as these are composed of earth quite bare and uncovered, they are easily sof tened by the water, and quickly washed away; so that the upper part of the bank being thus undermined, falls by its own weight into the river, and is carried off in prodigious quantities. But, when the river rises to any considerable height, it gently glides along the surface of those parts of the bank that shelve gradually downwards to* the water's edge ; which, being defended by the matted roots of the grass with which it is covered, scarcely sustains any damage at all; and is nearly the same after the water


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