The results of one man's experiments, or practice, whether of success or failure, should not be conclusive to another, unless all the circumstances are identical. These are ever varying from one farm to another; and only a right understanding of the natural laws or principles brought into use, can determine what is best in each case. Therefore, a description of the methods I have used, or any detailed suggestions I may give, as the result of experience, would not be worth much, unless tested by the well-ascertained rules applicable to them, which men of science and skill have adopted and proved, by the immensely extended draining operations in Great Britain, and those begun in this country. These are now given in elaborate treatises, and quoted in agricultural journals. But they should be made familiar to every farmer, in all their practical details, and with methods suited to our country, where labor is dear and land cheap, as contrasted with the reversed conditions in England, where the practice of "thorough-draining" has so generally obtained, and has so largely improved the conditions of both landlord and tenant. Your book will do this, and thus do a great good; for draining will greatly enlarge the productive capacity of our land, and, consequently, its value, while it will render labor more effective and more remunerative to the employer and the employed. The fact of increased production from a given quantity of land, by draining, being ascertained beyond question, and the measure of that increase, at its minimum, being more than the interest at six per cent. upon the sum required to effect it--even at $50 per acre--the question of expediency is answered. To the owner of tillage lands there is no other such safe, sure, and profitable investment for his money. He lodges it in a bank that will never suspend payments, and from which better than six per cent. dividend can be received annually. Very truly, yours, B. F. NOURSE. Hon. H. F. FRENCH, Exeter, N. H. STATEMENT OF SHEDD AND EDSON. BOSTON, February 1, 1859. DEAR SIR:--The plan for a system of thorough drainage, a copy of which we send you herewith, was executed for Mr. I. P. Rand, of Roxbury. An outfall was obtained, at the expense of considerable labor, by deepening the Roxbury and Dorchester Brook for a distance of nearly a quarter of a mile, about four hundred feet of which was through a rocky bottom, which required some blasting. The fall thus obtained was only about two inches in the whole distance.