*236 



AGRICULTURE. 



BOOK I, 



that the utmost attention is requisite to collect them ; and, 

 when they are collected, to preserve them from returning to 

 their simple state, which is ultimately gaseous or aerial. This 

 subject fully considered will shew the immense importance of 

 not letting any vegetable substance, if possible to avoid it, be 

 dried in the sun; but of collecting all organized bodies that can 

 foe found, such as leaves, weeds, peat, moss, &c. and forming 

 them into composts with calcareous matters, and other putres- 

 cent manures, as practised and explained by Lord Meadow- 

 bank *, and recommended by the Highland Society. It also 

 shews the immense advantage of soiling with clover, tares, or 

 lucern, and the great benefit of the turnip husbandry. Cal- 

 careous and mineral manures are most successfully applied to 

 lands containing vegetable matter, either chiefly or almost en- 

 tirely, as peat soils ; in the body of the soil, as arable grounds ; 

 or on the surface, as old pasture lands. Lime is also used on 

 ferruginous soils, which it frequently improves, unless the iron 

 exist in very great proportions. Some mineral manures are 

 also of advantage from the salts which they contain ; as lime 

 and gypsum are supposed to be by some, and as salt and soot 

 are known to be by every ingenious agriculturist f. 



* See also the Earl of Dundonald's Remarks on Chemistry and Agriculture. 



f So convinced am I of the great benefit to be derived from strewing salt on the 

 surface of grounds, that I hesitate not to say, that if the tax were removed and far- 

 mers allowed to use it, double the quantity of pasture would be produced annually.— 



