The farmer and mechanic. [volume] (Raleigh, N.C.) 1877-1885, 1878-06-20
Nitrogen in Agriculture.

by Lippincott x Co., Philadelphia,
is "a really valuable work. 1t Will
be priced most by those who are
engaged in the arts and manufac-
lures, but agriculturists will find
many things of interest connected
with the culture of the soil. Under
"Manure," we find nearly forty
pages compiled from the latest re-
liable authorities upon this subject.
We wish we could republlsh the en-
tire article for the benefit Of the
readers of the FARMER, but have
space for but a few extracts. Ad-
hitting that phosphoric acid. pot
ash, and nitrogen are the three
most important elements IN plant
food, it discusses the sources of
supply and the annual loss through
various channels. OF the former,
phosphoric acid and potash, II is
claimed that but little loss is sus-
tanned during the growing season
from fertile land, but the lnforma-
ton supplied IS to the loss of NJ
trogen is less complete. The nitro
gen lost to the farm will indeed be
ALWAYS greater han the nitrogen
sold. The extra loss occurs partly
during the making of the manure !;
this does not admit of general cal
culation, but will be greater or less
according to the management pur-
sued. There will further be an
important loss OF nitrogen IL the
drainage water. Ammonia is re-
tanned by soil with great persist
ence /; the nitrogenOus organic mat
ter of soils is also tolerably insolu-
BILE. Nitrates, on the other hand,
are retained by soil to only a small
extent, and being very soluble are
easily washed out by rain. AS am
monia is rapidly oxidized into nj
trio acid in a porous soil, and nj
%trogenous organic matter suffers
more slowly a similar change, very
considerable losses of nitrogen may
take place during winter drainage.
In the case of soils deficient in
porosity, or from other causes i'll
supplied with oxygen, little or no
loss of nitric acid will take place /;
but it seems probable from Schloes-
ing's experiments, that, nnder these
circumstances, the decomposition
of the heterogeneous matter will
yield free nitrogen which will be
equally lost to the soil.
We pass now to the imports of IA
farm, and will consider for it the
natural and very important import
rain. Rain contains nitrogen in
the form Of ammonia and in the
form of nitric and nitrous acid.
The ammonia present is merely dis
solved atmospheric ammonia, and
the rain simply returns to the earth
ammonia previously volatilized
from the eartE's surface. Ammo
MIA is, according to Schloes.ng,
principally yolatil;zed from the
ocean in tropical ATTITUDES from
thence, it is carried by the diffusion
Of gases and atmospheric currents
to every part of the globe. The
nitrates lost to the soil by drainage
finally reach the sea; here they feed
marine plants, which, in their turn,
sustain marine animals; the plants
and animals in their decay furnish
ammonia, which, diffusing into the
atmosphere, is carried over CONT
nents and becomes once more food
for terrestrial vegetation.
The nitrous and nitric acid of
rain are not derived from the earth,
but are actually generated in the
atmosphere, electric discharges
having the power of causing the
free oxygen and nitrogen of the air
to combine. The quantity Of COM
bined nitrogen thus generated is,
however, but small, and rain al
ways contains 0 nitrogen in the
form of ammonia than in the form
of nitric or nitrous acid. The
amount of nitrogen brought down
in the annual rainfall has been
many times determined; it appa-
rently varies very much. The
average of seventeen series of expe-
riments, made chiefly in Germany.
in each Of which the rainfall was
examined for a whole year, gives
9.45 pounds of nitrogen to one
English acre. The average rainfall
in these experiments was about 225
inches. A two years determine
ton at Rothamstead gave 7.47
pounds as the annual supply of nj
trogen by rain. Besides nitrogen,
rain supplies small quantities of
chloride of sodium, and other salts.
The rain at Valencia, on the west
coast of Ireland, would supply,
according to DR.. A. Smiths analv-
sis, II! pounds common salt per
acre for each inch of rain that fell.