Our Climaie and our Wheat- Crops. 201 
of Land Drainage," published in this 'Journal' in 1874. Dr. 
Voelcker determined not only the ammonia and the nitric acid 
in the drainage-waters, but also the whole of the mineral con- 
stituents. 
Dr. Frankland also, at his own request, was supplied with 
numerous samples, not only of the drainage-waters from the 
different plots of the permanent wheat-field, but of those col- 
lected at the depths of 20, 40, and 60 inches respectively, from 
the '■^ drain-gaucjes" already described; and also of the rain- 
water collected in the large gauge at Rothamsted. In all he 
analysed nearly 70 samples of rain-water, and more than 100 
of drainajre-waters so collected. He determined in them the 
carbon, the nitrogen in the different forms of combination in 
which it existed, and the chlorine. His results are published 
in full in the Sixth Report of the Rivers Pollution Commission, 
presented to Parliament in 1874. In that Report we have a 
complete history of the waters of Great Britain, both above 
ground and under ground. We have the composition of the 
rain, the changes it undergoes in passing over or through 
various geological strata, and its condition as it appears again in 
rivers and springs. 
The dates of collection of the samples of drainage-waters 
analysed by Dr. Voelcker ranged from December 1866 to 
December 1868 ; and those of the rain and drainage- waters 
analysed by Dr. Frankland from January 1868 to February 1873. 
More recently, the investigation has been continued in the 
Rothamsted Laboratory, and we have now a large number of 
results, which will be made the subject of a paper very shortly. 
In the meantime it will be sufficient for our present purpose to 
draw some illustrations from the already published results of 
Dr. Voelcker and Dr. Frankland. 
At the conclusion of our paper " On the Effects of the Drought 
of 1870 " (vol. vii., S.S. part 1, of this 'Journal'), we were enabled, 
by the courtesy of Dr. Voelcker and Dr. Frankland, none of 
whose results were then published, to point out how very large 
might be the loss of nitrogen from the land in the winter after 
the application of ammonia-salts in the autumn. And in our 
paper on the " Growth of Barley for Twenty Years in Suc- 
cession on the same Land," in this ' Journal,' vol. ix., S.S., part 2, 
p. 334 et seq., 1873, will be found tabular summaries of their 
results, and also a discussion of them. 
In the following Table (IX.) is given a summary of some of the 
results of Dr. Voelcker and Dr. Frankland, in a different form 
from that above referred to. The object of the arrangement now 
adopted is, not only to indicate how great may be the loss suffered 
by the passing away of the nitrogen of manures in the form of 
