The four items of the cost of making one rod of lateral drain are as follows: Digging the ditches - - - .43 Grading - - - .06 Tiles and laying - - - .21 Covering and filling - - - .10 - - -.80 cts. If the drains are placed at intervals of 40 feet, there are required 64 rods to the acre,—this at 80 cents per rod will make the cost per acre,—for the above items,—$51.20. How much should be allowed for main drains, outlets, and silt-basins, it is impossible to say, as, on irregular ground, no two fields will require the same amount of this sort of work. On very even land, where the whole surface, for hundreds of acres, slopes gradually in one or two directions, the outlay for mains need not be more than two per cent. of the cost of the laterals. This would allow laterals of a uniform length of 800 feet to discharge into the main line, at intervals of 40 feet, if we do not consider the trifling extra cost of the larger tiles. On less regular ground, the cost of mains will often be considerably more than two per cent. of the cost of the laterals; but in some instances the increase of main lines will be fully compensated for by the reduction in the length of the laterals, which, owing to rocks, hills too steep to need drains at regular intervals, and porous, (gravelly,) streaks in the land, cannot be profitably made to occupy the whole area so thoroughly.(22) Probably 7-1/2 per cent. of the cost of the laterals for mains, outlets, and silt-basins will be a fair average allowance. This will bring the total cost of the work to about $60 per acre, made up as follows: Cost of the finished drains per acre - - - $51.20 7-1/2 per cent. added for mains, etc. - - - 3.83 Engineering and Superintendence - - - 5.00 Of course this is an arbitrary calculation, an estimate without a single ascertained fact to go upon,—but it is as close as it can be made to what would probably be the cost of the best work, on average ground, at the present high prices of labor and material. Five years ago the same work could have been done for from $40 to $45 per acre, and it will be again cheaper when wages fall, and when a greater demand for draining tiles shall have caused more competition in their manufacture. With a large general demand, such as has existed in England for the last 20 years, they would now be sold for one-half of their present price here, and the manufacture would be more profitable. There are many light lands on retentive subsoils, which could be drained, at present prices, for $50 or less per acre, and there are others, which are very hard to dig, on which thorough-draining could not now be done for $60. The cost and the promise of the operation in each instance, must guide the land owner in deciding whether or not to undertake the improvement. In doubtful cases, there is one compromise which may be safely made,—that is, to omit each alternate drain, and defer its construction until labor is cheaper.