1840.] SENATE— No. 36. 91 



and that cultivation which readers the earth most accessible to 

 these great agents, will beyond question prove most efficient.* 

 I have already stated my conviction of the propriety and ex- 

 pediency of a rotation of crops, on the ground of the excre- 

 mentitious matter ejected by a plant being unfavorable to the 

 successive growth of the same plant or one of the same family 

 on the same land. This, then, is also to be kept in view. 



In my former report on the cultivation of spring wheat, I 

 expressed my opinion of the necessity of deep ploughing for 

 wheat, and the necessity of furnishing a fresh soil for its roots. 

 This has been fully confirmed by the experiments and success 

 of highly inteUigent and practical farmers. 



Recent English Improvements. — In my first report, too, I 

 had the pleasure of laying before the government the extraor- 

 dinary benefits produced by subsoil ploughing, and gave at 

 that time a model of Smith's subsoil plough. Since that time 

 the success which has attended this mode of cultivation, has 

 fully confirmed all the notions and theories which I then gave 

 on the subject ; and is effecting a revolution and an improve- 

 ment in the agriculture of England as extraordinary as has 

 ever taken place in any of the arts, and which bids fair in its 

 effects upon the agricultural welfare of the country, to rank 

 next to the introduction of steam into the mechanic arts. 



This improvement consists, in the first place, in a thorough 

 draining of the soil by under-ground drains, which are sunk to 

 the depth of three feet, and then filled up with loose stone to 

 the depth of a foot ; or the drain is made with tile resembling 

 half a circle in their shape, and laid down directly at the bottom 

 of the ditch. x\fter this is done, the soil is ploughed and the 

 ploughing is followed by a subsoil plough, which loosens the 

 lower substratum without bringing much of it to the surface. 

 At successive times more of this lower soil is mixed with the 

 top mould, and the cultivation is constantly deepened and the 

 ground enriched. On such soils, after careful cultivation, the 

 crops of wheat are in many cases actually trebled, and the val- 

 ue of the land is vastly increased. The philosophy of its oper- 



'* Appendix K. 



