104 



On Agricultural Mechanics. 



them : so far from that, they are very apt to be filled u}5 by the 

 treading of the horses in the ordinary cultivation of the land : they 

 are, in fact, suited only for the drainage of pasture-land. 



The most efficient drainage, as I have said, is that performed 

 by the hand, and in which broken stones or tiles are used ; and 

 when the subsoil-plough is used after it, this wall, there is no 

 doubtj prove the most economical also. 



2. Subsoil-Plough. 



We now come to the consideration of the subsoil -plough. This 

 implement, though only lately brought into prominent notice by 

 Mr. Smith, of Deanston, seems to have been used in many dis- 

 tricts of England long ago. Thus, in the Report of Lancashire, 

 by Dickson, I find the following notice of the '' miner or deep- 

 stirring plough :" — " This is another tool of the plough kind, 

 somewhat similar in its nature, which was introduced into the 

 county nearly about the same period as the trench-plough (* long 

 since,' seep. 157). It simply consists of a ploughshare firmly 

 fixed to a strong beam, by means of a strong sheath and handle, 

 without any mould-board. It is usually drawn by four or more 

 horses, being made to follow, in the furrow, the common plough, 

 so as to penetrate into, loosen, and stir up the undersoil without 

 turning it up, to the depth of from 8 to 12 inches below the tract 

 in which that plough had gone." 



A more accurate description of the way in which the imple- 

 ment is used than is contained in this paragraph of 1813 could 

 not be given now. The use of it did not, however, spread, doubt- 

 less because it was unaccompanied by that which must always 

 precede it — thorough drainage; and it was not till Mr. Smith 

 showed, on his farm at Deanston, the immense advantages fol- 

 lowing the adoption of both operations together, that either ob- 



