APPENDIX. 29 



will completely obviate the necessity of open or 

 covered ditches. Its utility too in clay soils, but 

 especially in many of our wet meadows, where the 

 upper surface is thin and resting upon a hard pan, 

 cannot admit of a question. It is of course designed 

 to follow in the furrow of a common plough. The 

 trenching of ground in considerable tracts in other 

 countries, and in gardens of our own, has been fol- 

 lowed with the best effects. Here the soil is dug 

 thoroughly to the depth of two or three feet; and at 

 the same time it is so managed, that the substratum 

 is completely loosened and turned over, and the 

 rich vegetable mould is returned again to the top, 

 where it was at the commencement of the operation. 

 These ploughs are adapted to operate in the same 

 way as this trenching by the spade. The increase 

 of crops in grounds thus managed has been always 

 an ample compensation for the labor. The loosen- 

 ing of the earth and the consequent removal of the 

 water and admission of the air, besides affording 

 room for the expansion of the roots, without doubt 

 by a chemical action, assists the nourishment and 

 growth of the plant. The great objection to deep 

 ploughing has always been, that the cold gravelly 

 pan was brought to the surface; the vegetable mould 

 buried beneath it ; and, that it required a great 

 length of time and an extravagant amount of manure, 

 to bring the land into a healthy and fruitful condition. 

 These models are copied from a late number of the 

 British Farmer's Magazine ; and I subjoin the ac- 

 counts which are therein given of them." 



" The most astonishing effects appear to have been 

 produced by a new agricultural implement, the in- 

 vention of Mr. Smith, of Deanster, near Sterling in 

 Scotland, called the Subsoil Plough. This machine 

 is a necessary accompaniment to draining; but when 

 that is done effectively, it seems calculated to render 

 the most sterile and unproductive soil fertile and 

 profitable. There is no difficulty more fatal to the 

 practical farmer than that of cultivating a thin shal- 



