The cost of extra harvesting will be more than repaid by the value of the extra fodder, and the increased cultivation and manuring are lasting benefits, which can be charged, only in small part, to the current crop. Therefore, if it will pay to plow, plant, hoe and harvest for 30 bushels of corn, it will surely pay much better to double the crop at a yearly extra cost of $5, and, practically, it amounts to this;—the extra crop is nearly all clear gain. The quantity of Wheat required to repay the annual charge for drainage is so small, that no argument is needed to show that any process which will simply prevent "throwing out" in winter, and the failure of the plant in the wetter parts of the field, will increase the product more than that amount,—to say nothing of the general importance to this crop of having the land in the most perfect condition, (in winter as well as in summer.) It is stated that, since the general introduction of drainage in England, (within the past 25 years,) the wheat crop of that country has been more than doubled. Of course, it does not necessarily follow that the amount _per acre_ has been doubled, large areas which were originally unfit for the growth of this crop, having been, by draining, excellently fitted for its cultivation;—but there can be no doubt that its yield has been greatly increased on all drained lands, nor that large areas, which, before being drained, were able to produce fair crops only in the best seasons, are now made very nearly independent of the weather. It is not susceptible of demonstration, but it is undoubtedly true, that those clay or other heavy soils, which are devoted to the growth of wheat in this country, would, if they were thoroughly under-drained, produce, on the average of years, at least double their present crop. Mr. John Johnston, a venerable Scotch farmer, who has long been a successful cultivator in the Wheat region of Western New York,—and who was almost the pioneer of tile-draining in America,—has laid over 50 miles of drains within the last 30 years. His practice is described in Klippart’s Land Drainage, from which work we quote the following: