always be built at about one fourth of the expence that these would cost-will answer all purposes equally well; and, if carefully built, may be kept in repair for any number of years at as small an expence as they could

be.

§ III.

Of feal, or earthen Dikes.

As feal-dikes are common enough in fome parts of this country, and are not, in many cafes, fo durable as I would seem to infinuate; and, as this is, in general, owing to the faulty manner in which they are built, it will be proper for me here to explain the manner in which these dikes may be built, fo as to ftand much longer than they usually do.

The greatest part of the dikes of this kind, that I have feen, are made of a confiderable thickness, with a ditch on each fide; the

heart

1

heart of the dike being made up with the earth that has been taken from thefe ditches, and only a thin wall, on each fide, is built of folid feal from top to bottom; the confequence of which is, that, as the loofe earth that is thrown into the middle of the dike fubfides much more than the 'feal on each fide, the top of the dike finks down, and, of course, the two fide-walls are preffed too much upon the infide, so as to bilge (fwell) out about the middle, and quickly crumble down to duft. To avoid this inconvenience, I have always chofen to build my dikes of this fort much thinner than ufual, they being only three feet and a half thick at the bottom, one foot, or a very little more, at top, and five feet high, taking care to have them built in fuch a manner, as that every fod, (feal), from top to bottom, binds the joinings of the others below it, with as much accuracy as the bricks in a well built wall; as will appear by examining

B

1

mining and comparing together (Fig. 1ft.) which represents a perpendicular section of this dike; (Fig. 2d.) a fide-view of the fame; and (Fig. 3d.) a perpendicular view of each row as it lies in the dike.

The manner in which the workman proceeds, fo as to effectuate all these joinings with the utmost accuracy and facility, is as follows: He begins by making a long rut, xx and xx (Fig. 3d.) with his spade, along each fide of the dike, turning his back towards the place where the dike is intended to be, fo as to make the cut of the feal flanting outward, as at xx (Fig. 1st. and 4th.): He then makes another rut, a z, (Fig. 3d.) parallel to the former, at the diftance of the length of the feal a from it, keeping his face towards the dike, fo as to flope inward, as at R (Fig. 4th.), which is neceffary, that the first row of feal may be allowed to be raised up with freedom. then cut into fods of a proper breadth,

It is

as at

the

the doted lines a (Fig. 3d.), which being raised up by the fpade, are then laid into the dike, with the graffy fide undermost, as at a (Fig. 1ft. 2d. and 3d.); the same letter always representing the fame feal, as viewed in different directions. The other fide being finished off in the fame manner, the up

per

furface of the whole courfe of feal is pared smooth, and clapped down with the back of the fpade, to prepare it for receiving another courfe above it. Another row of feal, bz, (Fig. 3d.) is then marked off, at the diftance of the breadth of that at b, (Fig. 1ft. and 3d.) from the former, the workman keeping his face ftill towards the dike; and the through-band feal B, on the opposite fide, having been first rightly laid, this is put a-cross the ends of these lengthways, fo as to form a fide-band, b (Fig. 2d. and 3d.) Another rut, cz, is then made, at the distance of the length of the feal c from the former; but, before it be raised,

it is neceffary to draw a rut in the line b z, with the back of the workman towards the dike, which gives it the form BAC, (Fig. 4th.) leaving a small triangular piece at S; so that, when it is put upon the dike, it at once affumes the pofition as marked at BAC, and thus allows the opposite fideband O to join quite closely to it; whereas, had it not got the rut at B (Fig. 4th.). it would have projected outward above, as at D; so that the feal O could not have joined it closely, but would have left a triangular opening in the heart of the dike, as marked in the two courses of feal below this, which would make the dike far lefs folid and compact than it is when managed in this way. In this manner the workmen proceed, always rutting the through-band rows of feal in both ends, but the fidebands only on one fide, beginning every course with those which go a-cross the dike; fo that, if the measures are taken exactly, and the whole be rutted by the line, they

may