332 Report of Experiments on the Groivth of Barley, 
from other considerations, we concluded, in opposition to the 
view we had previously been disposed to entertain, that the last- 
named of these, that is, evolution from the plant, did not take 
place. 
With regard to drainage, the previous results of Professor 
Way,* and especially the subsequent ones of the experiments 
conducted at Rugby under our superintendence for the Royal 
Sewage Commission,! led us to attribute great importance to 
that part of the subject. In the course of that inquiry we 
arranged for the collection of sixty-two samples of drainage- 
water, the partial analysis of which was conducted by Professor 
Way ; and, comparing the results with those on the corresponding 
samples of sewage, it was obvious that but a small proportion of 
the nitrogen of the sewage which was not obtained in the increase 
of produce was recovered in the drainage-water in the form of 
ammonia. We therefore arranged for the collection of some 
special samples for complete analysis, and especially for the 
determination of the nitric apid, if any, in both sewage and 
drainage-water. The results showed considerably more nitrogen 
in the drainage in the form of nitric acid than in that of am- 
monia. Indeed, it was obvious that a large proportion of that 
important manurial constituent of the sewage was drained away 
and lost. Satisfied for the time with this indication, it was not 
contemplated to follow up that part of our general inquiry until 
the question of the accumulation of nitrogen within the soil itself 
had first been investigated. 
After the publication, in 1864, of the results of the growth of 
wheat for twenty years in succession on the same land, the sub- 
ject of the composition of the crop, according to season and 
manure, was resumed ; and it was determined to examine both 
the soils and the drainage-waters from the different plots, to see 
whether there was, on the one hand an accumulation of nitrogen 
in the soil, and on the other a loss by drainage. The nitrogen 
was determined in the first 9 inches, the second 9 inches, and 
the third 9 inches ; or, in all, to a depth of 27 inches of soil. 
The results were given at the Meeting ot the British Asso- 
ciation for the advancement of Science at Nottingham, in 1866, 
and the following quotation from the abstract of that paper will 
indicate their general bearing : — 
" The accumulation of nitrogen from the residue of manuring 
* "On the Composition of the Waters of Land-Drainage and of Rain." 
(' Jourral Royal Agricultural Society of England/ vol. xvii. Part I.) 
t " On the Sewage of Towns" (Third Report and Appendices 1, 2, and 3, of 
the Royal Commission, 18(i5). Also — " On the Composition, Value, and Utilisation 
of Town Sewage " (' Journal of the Chemical Society,' New Series, vol. iv. ; entire 
series, vol. xix., ISlifi). 
