Our Climate and our Wheat-Crops. 203 
where ammonia-salts were applied than where they were not, 
but that there was a gradual increase in the amount thus drained 
awaj and lost, with the increase in the amount of ammonia-salts 
applied. 
Comparing the figures relating to the same plots in the 
second division with those in the first, it will be noticed how 
very much less, indeed how very small, is the quantity of 
nitrogen as nitrates in a given quantity of the drainage-water 
collected after the conclusion of the winter period. Not only 
have the autumn-sown manures already been subject to a great 
loss during the winter, but vegetation is now more active, and 
more and more rapidly takes up and utilises the nitrates, and 
so serves to arrest their passage downwards. Further, with the 
increasing growth, and the increasing temperature, evaporation 
is increased, and the proportion of the rainfall which drains 
away is diminished. In fact, so far as can be judged from the 
data at command, the amount of water passing through the soil 
will, in ordinary seasons, be several times as much during the 
first four or five months after autumn-sowing and before the 
commencement of active above-ground growth, as afterwards to 
harvest. In the case of the autumn-sowing of the ammonia-salts 
there is, therefore, not only a much larger quantity of nitrogen 
as nitrates in a given quantity of drainage-water, but there is 
also a much larger quantity of water passing as drainage, during 
the winter than afterwards. 
Lastly in regard to the results relating to the autumn-sown 
ammonia-salts, it will be observed that although the quantity 
of nitrogen as nitrates in a given quantity of the drainage-water 
collected after the winter, and after the commencement of more 
active growth, is very small, it is, as in the case of the samples 
collected during the winter, and sooner after the application,, 
the greater, the greater the amount of ammonia-salts applied. 
We have yet to notice the results obtained from the plot 
manured with nitrate of soda, which was always applied in the 
spring, and generally between the middle and the end of March. 
It is seen that the drainage from this plot was much richer in 
nitrates after the application of the nitrate in the spring than it 
was during the winter before the fresh application. Still, con- 
sidering the great solubility of the nitrate, the little power of the 
soil to retain it, the fact that a crop had been grown and re- 
moved since the previous application, and the great quantity 
of drainage passing during the winter, the average amount of 
nitrogen as nitrates in the samples collected in the autumn and 
winter months is greater than would be expected compared with 
that from the plots manured with the ammonia-salts in the 
autumn. j\or is the average amount in the drainage collected 
