368 Report of Experiments on the Growth of Barley, 
Not only, then, did a given amount of nitrogen, supplied as 
ammonia-salts, yield much more increase of produce in the years 
of its application, when applied in the spring for barley than 
when in the autumn for wheat, but a larger proportion of it 
was recovered in the increase of the spring-sown crop. 
The field experiments have further shown, that the at first 
unrecovered amount yielded scarcely any increase at all in 
succeeding years in the case of the wheat, but a considerable 
increase in that of the barley. 
With both crops, however, there remained a considerable 
amount of the supplied nitrogen not recovered in either at the 
first or the early succeeding increase of produce ; but there is 
obviously very much more to be otherwise accounted for in the 
case of the autumn-sown wheat than of the spring-sown barley. 
With regard to retention by the soil, the results of the analysis 
oT samples of the soils of many of the differently manured plots 
in the experimental wheat-field, taken in all down to a depth of 
27 inches, showed that a considerable amount of the nitrogen 
which had been supplied in the manure, and not recovered in 
the increase of crop, was accumulated within the soil ; but it 
was concluded that a larger proportion remained unaccounted 
for to the depth examined, than was there traceable, and that 
some of this had passed off by the drains, and some into the 
lower strata of the subsoil. 
With regard to loss by drainage, numerous analyses, by Dr. 
Voelcker and Dr. Frankland, of the drainage waters from the 
Rothamsted experimental wheat-plots, confirmed the supposition 
that there had been a considerable loss of the nitrogen of the 
manures in that way. They showed that the quantity of nitrates 
in the drainage-water was the greater the greater the amount of 
ammonia-salts applied ; and that, after autumn-sowing, the quan- 
tity Avas very much greater in the winter than subsequently in 
the spring and summer. 
Calculation showed that, for every 1 part of combined 
nitrogen per 100,000 parts of drainage-water, there will be a 
loss of 2^ lbs. of nitrogen per acre for every inch of rain 
passing beyond the reach of the roots as drainage of that strength. 
In one case of winter-drainage, after an application of 600 lbs. 
of ammonia-salts per acre in the autumn. Dr. Frankland's 
analysis showed 7*841 parts of nitrogen per 100,000 parts of 
water, corresponding to a loss of nearly 18 lbs. of nitrogen per 
acre, provided (which, however, is not probable) that an inch 
of rain had passed as drainage of that strength. 
As would be expected, as the nitrate of soda was, even for 
wheat, always sown in the spring, the autumn and winter- 
drainage from the nitrated plot always contained much less 
nitrogen than that collected at the same date from the plots 
