597 
‘ 
In my letter published in the Times of September 29, last year, I stated that the 
‘geason of 1870~71 was, for artificial manures, much less favorable, but for farm-yard 
manures considerably more favorable than the average; and that, consequently, 
the calculated average from my produce, which is considerably influenced by 
the results obtained by artificial manures, would probably give a figure too low 
for the average produce of the country at large in 1871; while, on the other hand, 
as the season of 1871~72 was, compared with the average, more unfavorable for 
farm-yard than for artificial manures, the figure derived from the experimental results 
of 1872 would probably be too high for the average yield of the country in that year. 
A correction was accordingly made, and the imports of the year have shown that the 
estimate of the average crop of the country so arrived at must have been extremely 
near to the truth. 
In the present season the unmanured produce is higher than in 1872, and considera- 
bly higher than in 1871. On the other hand, reducing the produce in each case to 
bushels of 61 pounds, that by farm-yard manure is nearly 7 bushels per acre lower than 
in 1872, and nearly 13 bushels lower than in 1871; and the mean produce of the three 
artificially manured plots is more than 8 bushels below that of last year, but almost 
identical with that of 1871. 
Taking the mean of the produce without manure, with farm-yard manure, and of the 
three artificial manures taken as one, we have 222 bushels of grain per acre, of 57.4 
pounds per bushel, whichy reckoned at 61 pounds per bushel, represents only 21 bush- 
els. This is from 4 to 5 bushels less than the average taken in the same way last year, 
and nearly 7 bushels less than the average of twenty-two years. In fact the produce 
by farm-yard manure and by the various artificial manures agrees very closely with that 
under the same conditions in the very bad season of 18€7. 
Reduced to 61 pounds per bushel, the average produce of the selected plots in the 
experimental wheat-field in 1873 is about 24 per cent. below the average of twenty-two 
years. Much of this great deficiency is due to the fact that there was, in all, about 
double the average fall of rain during the four months of October, November, Decem- 
ber, and January, the effect of which would be to wash beyond the reach of the roots 
a large amount of the nitrogenous manure which had been applied in the autumn. 
It is established that that most important ard costly constituent of manure, nitrogen, 
especially when applied in the soluble form of ammonia, is largely converted into ni- 
trates in the soil, and is, in that condition, washed away into the drains or the subsoik 
when there is an excess of rain. The loss of effect thus arising is strikingly illustrated 
by a comparison of the produce of the two plots, No. 7 and No.9. Both received the 
same amount of nitrogen per acre, which was applied as ammonia salts in the autumn 
to plot 7, and as nitrate of soda in the spring to plot 9. The result was that while the 
autumn-sown ammonia salts yielded 22 bushels, the spring-sown nitrates yielded 
nearly 33 bushels. Again, another plot which received the same amount of ammonia 
ce as plot 7, but applied in the spring instead of the autumn, yielded nearly 33 
ushels. 
The loss of the nitrogen of manure by winter drainage would be the greatest where 
guano, ammonia salts, or other very soluble nitrogenous manure was sown in the 
autumn, less where farm-yard manures are employed, and still less where wheat was 
grown after. 
* FoRESTRY.—An “ international congress of land and forest cultur- 
ists’ held in Vienna in September, presided over by the Austrian 
minister of agriculture, passed resolutions petitioning the Austrian 
government to take measures for inaugurating international treaties 
with other European states intended to secure the protection of birds 
useful in agriculture; another series, declaring the lack of scientific 
basis for land and forest culture, and the necessity of official publica- 
tions of exact statistical comparative data illustrating the status and 
progress of each country in these departments of industry ; and a third 
relative to the necessity of action toward forest preservation, as fol- 
lows: 
1. We recognize the fact that, in order to effectually check the continually increas- 
ing devastation of the forests which is being carried on, international agreements are 
needed, especially in relation to the preservation and proper cultivation (for the end 
in view) of those forests lying at the sources and along the courses of the great rivers, 
since it is known that, through their irrational destruction, the results are great 
decrease of the volume of water, causing detriment to trade and commerce, the filling 
up of the river’s bed with sand, caving in of the banks, and inundations of agricultu- 
ral lands along its course. ; 
2. We further recognize it to be the mutual duty of all civilized lands to preserve 
