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desired point, we fix, at the angle of the square, the point on the base-line from which we are to measure the length of the offset. The next step is to find, (by the scale,) the distance of this point from the nearest end of the baseline, and from the point sought. Then measure off, in the field, the corresponding distance on the base-line, and, from the point thus found, measure on a line perpendicular to the base line, the length of the offset; the point thus indicated will be the locality sought. In the same manner, find another point on the same drain, to give the range on which to stake it out. From this line, the drains which run parallel to it, can easily be found, or it may be used as a base-line, from which, by measuring offsets, to find other points near it.

The object of this staking is, to find, in an inexpensive and easy way, the precise position of the drains, for which it would be otherwise necessary to grope in the dark, verifying our guesses by digging four-foot trenches, at random.

If there is a silt-basin, or a junction a short distance be.ow the point where the water shows itself, this will be the best place to dig. If it is a silt-basin, we shall probably find that this has filled up with dirt, and has stopped the flow. In this case it should be cleaned out, and a point of the drain ten feet below it examined. If this is found. to be clear, a long, stout wire may be pushed up as far as the basin and worked back and forth until the passage is cleared. Then replace the tile below, and try with the wire to clean the tiles above the basin, so as to tap the water above the obstruction. If this cannot be done, or if the drain ten feet below is clogged, it will be necessary to uncover the tiles in both directions until an opening is found, and to take up and relay the whole. If the wetting of the ground is sufficient to indicate that there is much water in the drain, only five or six tiles should be taken up at a time, cleaned and relaid,—commencing at

the ower end,-in order that, when the water con mences to flow, it may not disturb the bottom of the ditch for the whole distance.

If the point opened is at a junction with the main, examine both the main and the lateral, to see which is stopped, and proceed with one or the other, as directed above. In doing this work, care should be taken to send as little muddy water as possible into the drain below, and to allow the least possible disturbance of the bottom.

If silt-basins have been placed at those points at which the fall diminishes, the obstruction will usually be found to occur at the outlets of these, from a piling up of the silt in front of them, and to extend only a short distance below and above. It is not necessary to take up the tiles until they are found to be entirely clean, for, if they are only onehalf or one-third full, they will probably be washed clean by the rush of water, when that which is accumulated above is tapped. The work should be done in settled fair weather, and the ditches should remain open until the effect of the flow has been observed. If the tiles are made thoroughly clean by the time that the accumulated water has run off, say in 24 hours, they may be covered up; if not, it may be necessary to remove them again, and clean them by hand. When the work is undertaken it should be thoroughly done, so that the expense of a new opening need not be again incurred.

It is worse than useless to substitute larger sizes of tiles for those which are taken up. The obstruction, if by silt, is the result of a too sluggish flow, and to enlarge the area of the conduit would only increase the difficulty. If the tiles are too small to carry the full flow which follows a heavy rain, they will be very unlikely to become choked, for the water will then have sufficient force to wash them clean, while if they are much larger than necessary, a deposit of silt to one half of their height will make a broad,

flat bed for the stream, which will run with much less force, and will be more likely to increase the deposit.

If the drains are obstructed by the roots of willows, or other trees, the proprietor must decide whether he will sacrifice the trees or the drains; both he cannot keep, unless he chooses to go to the expense of laying in cement all of the drains which carry constant streams, for a dis tance of at least 50 feet from the dangerous trees. The trouble from trees is occasionally very great, but its occurrence is too rare for general consideration, and must be met in each case with such remedies as circumstances sug gest as the best.

The gratings over the outlets of silt-basins which open at the surface of the ground, are sometimes, during the first year of the drainage, obstructed by a fungoid growth which collects on the cross bars. This should be occasionally rubbed off. Its character is not very well understood, and it is rarely observed in old drains. The decomposition of the grass bands which are used to cover the joints of the larger tiles may encourage its formation.

If the surface soil have a good proportion of sand, gravel, or organic matter, so as to give it the consistency which is known as 66 loamy," it will bear any treatment which it may chance to receive in cultivation, or as pasturo land; but if it be a decided clay soil, no amount of draining will enable us to work it, or to turn cattle upon it when it is wet with recent rains. It will much sooner become dry, because of the drainage, and may much sooner be trodden upon without injury; but wet clay cannot be worked or walked over without being more or less puddled, and, thereby, injured for a long time.

No matter how thoroughly heavy clay pasture lands may be under-drained, the cattle should be removed from them when it rains, and kept off until they are compara tively dry Neglect of this precaution has probably led

to more disappointment as to the effects of drainage than any other circumstances connected with it. The injury from this cause does not extend to a great depth, and in the Northern States it would always be overcome by the frosts of a single winter; as has been before stated, it is confined to stiff clay soils, but as these are the soils which most need draining, the warning given is important.

CHAPTER VI.

WHAT DRAINING COSTS.

Draining is expensive work. This fact must be accepted as a very stubborn one, by every man who proposes to undertake the improvement. There is no royal road to tile-laying, and the beginner should count the cost at the outset. A good many acres of virgin land at the West might be bought for what must be paid to get an efficient system of drains laid under a single acre at home. Any man who stops at this point of the argument will probably move West, or do nothing.

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Yet, it is susceptible of demonstration that, even at the West, in those localities where Indian Corn is worth as much as fifty cents per bushel at the farm, it will pay drain, in the best manner, all such land as is described in the first chapter of this book as in reed of draining, Argu ments to prove this need not be based at all on cheapness of the work; only on its effects and its permanence.

In fact, so far as draining with tiles is concerned, cheap ness is a delusion and a snare, for the reason that it implies something less than the best work, a compromise between excellence and inferiority. The moment that we come down from the best standard, we introduce a new element into the calculation. The sort of tile draining which it is the purpose of this work to advocate is a system so com

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