Second in importance to draining only, are the subjects of “subsoil and trench ploughing,” operations which are also to be performed at this season of the year—­and a chapter upon which concludes the first volume of Mr. Stephens’s work.  Those who are acquainted with the writings of Mr. Smith of Deanston, and with the operations of the Marquis of Tweeddale at Yester, will duly estimate the importance, not merely to the young farmer himself, but to the nation at large, of proper instruction in regard to these two important operations—­in the mode of economically conducting them—­in the principles upon which their beneficial action depends—­and in the circumstances by which the practical man ought to be regulated in putting the one or the other, or the one rather than the other, in operation upon his own land.  Our limits do not permit us to discuss the relative merits of subsoil and trench ploughing, which by some writers have unwisely been pitted against each other—­as if they were in reality methods of improving the land, either of which a man may equally adopt in any soil and under all circumstances.  But they, in reality, agree universally only in this one thing—­that neither process will produce a permanently good effect unless the land be previously thorough-drained.  But being drained, the farmer must then exercise a sound discretion, and Mr. Stephens’s book will aid his judgment much in determining which of the two subsequent methods he ought to adopt.  The safer plan for the young farmer would be to try one or two acres in each way, and in his after procedure upon the same kind of land to be regulated by the result of this trial.  Mr. Stephens expresses a decided opinion in favour of trench-ploughing in the following passages:—­

“I have no hesitation in expressing my preference of trench to subsoil ploughing:  and I cannot see a single instance, with the sole exception of turning up a very bad subsoil in large quantity, in which there is any advantage attending subsoil, that cannot be enjoyed by trench ploughing:  and for this single drawback of a very bad subsoil, trenching has the advantage of being performed in perfect safety, where subsoil ploughing could not be, without previous drainage.

“But whilst giving a preference to trench ploughing over subsoil, I am of opinion that it should not be generally attempted under any circumstances, however favourable, without previous thorough-draining, any more than subsoil ploughing; but when so drained, there is no mode of management, in my opinion, that will render land so soon amenable to the means of putting it in a high degree of fertility as trench ploughing.”—­Vol. i. p. 664.