Experiments upon Wheat, Barley, and Swedes. 321 
The corresponding percentage proportions, thus calculated, are given in the 
last column : — 
Top-Dressings on Wheat. 
Nitrate of Soda per Acre. 
Number of 
Experimental 
. Plots. 
Average Increase 
of Corn 
per Acre over 
Unmanured Plots. 
Proportion of 
Nitrogen 
in Manure to Nitrogen 
in increase of Corn. 
11 
416-5 
100 : 31-9 
3 
8G3- 
100 : 33-1 
168 lbs., with 336 lbs. super-) 
336 lbs., with 672 lbs, super-^ 
168 lbs., with 336 lbs. super-| 
Ditto ditto 
2 
2 
4 
2 
5.52-5 
1000 
870 
826 
100 : 42-3 
100 : 38-3 
100 : 66-7 
100 : 63-3 
The hest results in this series are those obtained by the application of 
Is cwi. nitrate with 3 cwts. superphosphate, in one case an amount of nitrogen 
■equal to two-thirds of that in the manure appearing in the increase of grain, 
leaving out of calculation that in the excess of straw produced. It is only 
when an amount of nitrogen equal to 23 per cent, of that in the nitrate 
applied appears in the increase of grain tliat the cost of the manure is 
defrayed, supposing the nitrate is bought at 16s. 6d. per cwt., and the grain 
sells at 5s. per bushel. So if 1^ cwt. of nitrate has been employed, about 
5 bushels of extra grain are demanded ; the worst of the above results shows 
just 7 bushels. 
Appendix II, " 
It has been observed that where wheat is allowed abundance of room, 
the growing plant speedily assumes a dark-green vigorous appearance, very 
similar to that of wheat manured with some highly nitrogenous manure. This 
effect is not contined to any particular season, but may be seen wherever thin 
sown can be contrasted with thicker sown wheat. This similarity in appear- 
ance between a thin plant of wheat and a crop which has been top-dressed 
v^ith nitrate of soda suggests the idea that in both cases the improvement is 
due to a more liberal supply of nitrogen to the individual plants. Is it not 
also worthy of note, that both thin planted crops and those top-dressed with 
nitrate of soda are more subject to the attacks of parasitic fungi than crops 
more ordinarily cultivated ? So much so is this the case that many farmers 
object to top-dress for fear of inducing mildew, while others shun thin seedino- 
for a similar reason. The relations of thin sown crops to the amount of 
nitrogen contained in the grain was strikingly exempli6ed in 1868. Professor 
Church, in Vol. L, ' Practice with Science,' called attention to the amount of 
nitrogen found in different samples of wheat. On examining almost any 
variety of this grain, it was observed that the sample might be readily divided 
into three parts : the first containing all the horny or translucent (" strong ") 
grains ; the second, those of a medium appearance ; and lastly, a class of 
softer, opaque, dull-looking grains. Analysis of each section of a sample thus 
divided showed that the amount of nitrogen contained in the transhicent grains 
considerably exceeded that found in the opaque grains ; and this was rendered 
the more striking when the nitrogen was calculated into its equivalent of 
albuminoids. The following table, from Professor Church's paper on thifj 
subject, is illustrative of the above fact : — 
