824 = 558 Influence of Chemical Discoveries on 
The following Table, by Messrs. Lawes and Gilbert, sho 
the amount of nitrogen recovered, and the amount not recoven 
in the increase of the crop for 100 supplied in manure, to whi 
and to barley respectively : the result being in each case 1 
average over a period of 20 years. 
Table II. — Nitrogen kecoveeed, and not becoveeed, in the 
Increase of Produce, for 100 supplied in Manure. 
Manuring, quantities per Acre per Annum. 
For 100 Nitrogen i 
Manure. 
Recovered Kot] 
in I Kopvc/I 
Increase, in Incn 
Wheat, 20 years, 1852-1871. 
Complex Mineral Manure, and 41 lbs. Nitrogen, as Ammonia 
82 lbs. 
82 lbs. 
as Nitrate 
Bablet, 20 years, 1852-1871. 
ComplexMineralManm-e, an(141 lbs.NitTOgen,asAmmonia 48-1 | 51" 
Proportion of 
nitrogen un- 
recoverable. 
Notwithstanding the great effect produced by the nitrogen s 
manures, two-thirds of the nitrogen supplied was unrecove 1 
in the increase of crops when the ammonia-salts were appliet i 
wheat ; the application having been made in the autumn. VVl: , 
however, nitrate of soda was used, which is always applied i 
the spring, the quantity left unrecovered was not much m e 
than half that supplied. With barley, also, the manuring r 
which takes place in the spring, there is again nearly half e 
nitrogen supplied in the manure recovered in the increase, ; 1 
therefore little more than half left unrecovered. 
The question Avill naturally be raised, what Jbecomes of e 
one-half or two-thirds of the nitrogen which is not recovt d 
in the increase of the crops ? The examination of some 0 
samples by myself, and a number of independent dctennii- 
tions by Dr. Frankland, of the drainage-water from the exp i- 
mental wheat plots which yielded the preceding results, th * 
much light on this loss. 
The following Table contains a summary of some of * 
more important results obtained by Dr. Frankland and ; ■- 
self. i 
i 
