“The partially dried roots contained: Moisture 5.06 Organic matter* 31.94 Mineral matter 63.00 ------- 100.00 ======= * Containing nitrogen .804 “An acre of this soil, six inches deep, produced 3 tons, 7 cwts. 65 lbs. of clover-roots, containing 61 lbs. of nitrogen; that is, there was very nearly the same quantity of roots and nitrogen in them, as that furnished in the soil from the brow of the hill. “The roots, moreover, yielded .365 per cent of phosphoric acid; or, calculated per acre, 27 lbs. “In the partially dried soil, I found: Moisture 4.70 Organic matter* 10.87 Mineral matter† 84.43 ------- 100.00 ======= * Containing nitrogen .405 Equal to ammonia .491 † Including phosphoric acid .321 “According to these determinations, an acre of soil from the bottom of the hill, contains: Tons Cwts. Lbs. Nitrogen in the organic matter of the soil 2 2 0 Nitrogen in clover-roots of the soil 0 0 61 --- --- --- Total amount of nitrogen per acre 2 2 61 === === === “Compared with the amount of nitrogen in the soil from the brow of the hill, about 11 cwt. more nitrogen was obtained in the soil and roots from the bottom of the hill, where the clover was more luxuriant. “The increased amount of nitrogen occurred in fine root-fibres and other organic matters of the soil, and not in the coarser bits of roots which were picked out by the hand. It may be assumed that the finer particles of organic matter are more readily decomposed than the coarser roots; and as there was a larger amount of nitrogen in this than in the preceding soil, it may be expected that the land at the bottom of the hill, after removal of the clover, was in a better agricultural condition for wheat, than that on the brow of the hill.” CHAPTER XXVI. EXPERIMENTS ON CLOVER-SOILS FROM BURCOTT LODGE FARM, LEIGHTON BUZZARD. “The soils for the next experiments, were kindly supplied to me, in 1866, by Robert Valentine, of Burcott Lodge, who also sent me some notes respecting the growth and yield of clover-hay and seed on this soil. “Foreign seed, at the rate of 12 lbs. per acre, was sown with a crop of wheat, which yielded five quarters per acre the previous year.