Experiments on the Growth of Wheat. 
33 
or some combination of thom, is tho most cffoctive ; and by 
means of the <^uano (experiment 5), which is the cheapest so- 
called artificial manure containing a large proj)ortion both of 
nitrogen and phosphates, we ai'e enabled to judge whether 
increase of crop can be obtained profitably by the use of such a 
combination. 
The results obtained in each of the four years in which the 
manures were applied, in the two succeeding years without manure, 
and over the total period of six years, are given in a series of 
tables as follow (pp. 34-38) : — 
Table I. The dressed corn per acre, in bushels and pecks, and 
the total corn per acre, in lbs. 
Table II. The straw (chaff, &c.) per acre, in ll)s., and the total 
produce (corn and stiaw) per acre, in lbs. 
Table III. The increase per acre, by manure, of dressed corn 
(bushels and pecks), and of total corn (lbs.). 
Table IV. The increase, per acre, of straw (chaff, &c.), in lbs., 
and the increase of total produce (corn and straw), in lbs. 
Table V. The weight, per bushel, of dressed corn, and the 
proportion of corn to 100 of straw in the produce, and in the 
increase by manure. 
In the first year of the experiments the unmanured plot gave 
about 32^ bushels of dressed corn, and nearly 43 cwts. of straw 
per acre ; the farmyard-manure gave only about 30f bushels of 
dressed corn, but rather more than 56 cwts. of straw ; and the 
greatest increase obtained by any of the manures was between 
4 and 5 bushels of dressed corn, and between 15 and 16 cwts. of 
straw. It is obvious that, even unmanured, the condition of the 
land was almost as high as was compatible with the healthy 
growth and proper ripening of the crop — that it was, in fact, 
scarcely in a state to require manure at all, and therefore not in a 
condition to show very prominently the characteristic action of 
the different manures employed. The best preparation would 
have been to grow a crop of wheat over the whole field without 
manure, before commencing with the special manures. It is 
unfortunate, too, that the manures were only applied during four 
consecutive years ; that during the two succeeding years, without 
manure, the seasons were very unfavourable, and the land had 
become somewhat foul ; and that the experiments were entirely 
stopped before the influence of the manures had ceased, and their 
whole effect been ascertained. 
Notwithstanding the unfavourable circumstances above men- 
tioned, the results of the experiments at Rodmersham are very 
valuable ; and, taking into consideration the very different con- 
dition of the land, they are entirely confirmatory of the con- 
clusions that have been arrived at from experiments made 
VOL. XXIII. D at 
