The farmer and mechanic. [volume] (Raleigh, N.C.) 1877-1885, 1878-05-23

preceding show that, by this new
way also, one acre Of land receives
three pounds Of nitrogen at the
most. Nitric acid, therefore, ex-
plains no better than ammonia the
excess Of nitrogen IN the crops.
But. it is urged, there may exist
in the atmosphere, some nitrogen
Gus substance eminently asslmlla-
BILE. which is condensed by am
water. and which has hitherto es-
caped ANALYSIS. Notwithstanding
the utter vagueness of this obJec-
ton, | have wished to reply to II
by direct experiment. | haze IN
stituted two similar growths IN
boxes, placed under shelter; one of
them was watered with RAIN water
collected by a pulviometer Of equal
surface to that of the box, and
placed apart; the other received
similar quantities of perfectly pure
distilled water. The crop with
distilled water was nearly as large
as that obtained with rain water.
1t is, therefore, evident that ram
water contained nothing susccptl-
bic of influencing the Development
Of vegetables.
But. since it has been desired to
give this importance to the essen
tial products the air may yield to
the soil, it will be permitted to me,
on the other hand, to consider those
which the soil yields to the atmos-
phere: and this time it Is from my
adyersarics themselves that | bor-
row the basis Of my arguments.
NJ. Boussingault had the idea OF
collecting the snow from the sur
face of the ground and the terrace
of a garden. A litre of water from
the first contained 0.001. or. OF
nitrogen, while that from the ter
race contained O.0103 OF. 1t IS
certain, therefore, that cultivated
soil constantly loses nitrogen. 1T
we suppose that the layer of snow
examined by NJ. Boussingault had
a thickness of only O.O1 m, it con-
tanned IN one acre $50 pounds OF
nitrogen lost to the soil. We see,
then, that the losses the soil is ca
pable of experiencing are quite as
important as the gains it may de-
rive from the atmosphere. We must
necessarily, then, have recourse to
elementary nitrogen to explain the
excess In the crops.
But here another subject of dis
cussion presents itself; the nitrogen
of the airs it absorbed naturally
bv plants, as | have always main
tanned, or does it take place, as re-
Gently suggested, only by the inter
medium Of notification previously
accomplished in the soil, which
would thus be a real artificial nltre-
bed? Doubtless, III certain cases,
important quantities of nitrates
may be produced in the soil; but
none the less persist in saying that
ni~trificatiol cannot account for the
excess of nitrogen in the crops.
, For the 1872 pounds to have pene-
trated into the lucern by this chan
mel, it would have been necessary
to engage 1,156 pounds of nitric
acid, which, itself, to be saturated,
must have combined with 1,540
pounds Of bases. These l,54C
pounds of bases should be found III
, the crops; but the latter produced,
! upon combustion, only 1,525 pounds
, of ashes, of which the bases formed
1Ol pounds. There is, then, al
, least half the excess that the by
pothesis of notification can moi
explain.
Besides, if it were SO, if the III.
| trogen of the crops came from the
nitrogen formed in the soil, is i
! not evident that an artificial add
ton of nitrates would produce the
same effect as a natural formation,
: Now there exist, in fact, some
t crops, that of wheat, for example
the addition of nitrates to whicl
/ increases the yield. But there ar,
: others, as you may see for your
selves by inspecting the experiment
: tai field, upon which nitrates excl
e else no influence. Peas. for exam
d pie, have not assimilated NOR
n nitrogen with a strong manure o
nitrates than without the addition
t of any heterogeneous compound. |
/ is then quite evident that If, IL
} certain cases, natural nitriticatlol
/ can play a definite part, it may, o.
It the other hand, serve as a genera
explanation of the excess of nitro
l. gen in the crops, and that the tru
II and great origin of this nitroge,
r resides in the atmospheric nitroge,
l. directly absorbed.
Is And moreover. what is there, i
,e a theoretical point of view, SO re