THE DRAINAGE OF FARMS. 95 



to remain so till the water has been voided from the upper 

 stratum of the soil, the lower part may then be cut out with 

 more safety from falling in. The stones should not be filled 

 nearer to the surface than 18 inches, leaving 16 inches free for 

 deep ploughing. 



&quot; The upper surface of the stones having been made straight 

 and uniform, the whole should be neatly and closely covered 

 with a thin thatch or turf, cut from the adjoining surface or 

 brought from some suitable place. Strict attention to the correct 

 execution of this operation is of the greatest importance, as many 

 drains are ruined at once from the running in of the loose earth. 

 Thick turfs are objectionable, from the difficulty of getting them 

 to fit close. Straw, rushes, broom, whins, and other like mate 

 rials, are very objectionable, affording; no certain or uniform 

 security, and forming a receptacle for vermin ; peat moss, in a 

 thin layer, well beat down, may be used to advantage. When 

 the deepest ploughing has been executed, there should always 

 remain a firm crust of earth undisturbed over the stones of the 

 drain ; and no surface water should ever have access to the free 

 way of a drain by any direct opening, but should find its way 

 by percolation or filtration through the subsoil, and should 

 always enter by the sides of the drains. It may be of advan 

 tage to tread or beat down closely the first two inches of soil 

 put over the turf, in order to form the permanent crust.&quot; 



The making of drains is a matter which requires great skill 

 and experience. So important and expensive an operation 

 should be executed with the greatest care. The most thorough 

 and permanent mode of doing it will be found, in the end, the 

 most satisfactory and the least expensive. The science and 

 skill of an experienced engineer will be often found requisite to 

 lay out the work, and to determine the levels, where it is to be 

 undertaken to any great extent, either by individuals or com 

 panies ; and this class of men, now so rare among us, may, I 

 hope, presently appear. The supply of such professional men, 

 whose services would be of the greatest utility in many cases, is 

 a prominent object, to which I should look forward in the estab 

 lishment of seminaries for agricultural education. There has 

 been, many times, a great waste of labor and money, and most 

 mortifying disappointments, where such operations have been 

 imperfectly and hastily executed, or undertaken without expe- 



