for Tae:it.)j Years in succession on the same Land. 
339 
receives only half the quantity of nitrogen annually, but in the 
form of ammonia-salts, which had been applied in the autumn. 
During the rest of January (1872) some of the drains ran very 
frequently, and nearly all of them more than once ; in March, 
again, many of them ran twice, and on May 18th there was a 
discharge from all excepting that from the dunged plot. In 
fact, in January there was a great excess of rain ; in February a 
fair amount ; in March considerably more than the average ; in 
April nearly the average ; and in May a considerable excess. 
Up to the middle of May, therefore, the soil had been subjected 
to an unusual washing out ; whilst growth would then have 
advanced considerably, and the roots would have established 
command over the soluble matters within the soil. The result 
is, that the amount of nitrogen in the drainage at that date 
was extremely small in all the cases of autumn manuring by 
ammonia-salts ; but it was very much greater where the nitrate 
had been applied on March 7th. It is true that the actual amount 
of nitrogen as nitrates and nitrites in a given quantity of the 
drainage from the nitrated plot was less in May, after the sowing 
of the manure in March, than it was in January, when no nitrate 
had been sown, and a crop had been grown since the application 
of the manure in the previous March ; but in May the quantity 
in the drainage from the nitrated plot was very many times 
greater than in that from either of the plots which had been 
manured with ammonia-salts, whilst in January it was less. 
After the collection on May 18th, there was about one-third of 
an inch of rain before the end of the month, bringing up the total 
to notably more than the average. In June, again, there was 
an excess of rain, more especially during the first third of the 
month ; on June 9th a few of the drains ran, and on June 11th most 
of them, though only slowly. Samples of the drainage from 
eight of the plots were sent to Dr. Frankland ; and although in 
three of them a very small amount of nitrogen as nitrates and 
nitrites was found, the Table shows that there was none whatever 
in that from either of the plots to which the results there given 
refer. This is a very interesting fact ; and it is doubtless 
accounted for, in part by the previous washing out of the soil, 
and in part by the extent to which the growing crop would, by 
the middle of June, have availed itself of assimilable nitrogen 
within the soil. 
It only remains to add, in reference to the season thus far 
referred to, that, after such considerable loss by drainage during 
the winter, the crops in the experimental wheat-field which had 
been manured with mineral manure and ammonia-salts, applied 
in the autumn, were considerably below the average obtained 
under corresponding conditions in other years, whilst the produce 
"VOL. IX. — S. S. 2 A 
