Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1882-02-25

fertilizer, and containing, as it does, Two
essential ingredients of plants lcalcii N
and phosphoric acid), its value as fertlI-
izer ia quite high. A substance is found
10 the mineral world which is almost
identical with the earth of bones, only
differing from it by containing about three
per cent. more OF calcium. 1t is known as
apatite or phosphorite, and occurs In some
countries in great quantities, both in beds
and in mineral veins Of granite and slate
rock also to some extent in certain iron
ore. 1t sometimes occurs mixed with lime
stone carbonate Of calcium), and such
mineral makes most excellent fertilizer.
The acid phosphate of calcium contains
about twenty-three per cent less lime than
does the neutral phosphate. 1t is found in
considerable quantities in ANNA, urine, and
seems to be an important constituent of all
liquid animal manures.
COMPOUNDS OF MAGNESIUM.
The carbonate of magnesium is taste.
less, earthly compound, which is found in
considerable quantities in some mineral re-
gions. Itlargely occurs with limestone ia
the magnesium or dolernite limestones. It
also constitutes large per cent. of the ash
composition of some plants. Magnesium
carbonate is an almost universal ingredient
of soils its absorptive power is very great
and soils impregnated with this substance
have been termed "cold soils" It, like
| carbonate of calcium, is soluble in carbonic
acid, whose action, more than that of any
other acid, renders the magnesium avail
| able to the plant roots. Caustic magnesia
may be prepared from the carbonate
| by heating to redness in the open
! air. Magnesium does not occur in this
caust;c state in water, but is often found
in large quantities during the burning of
| dolomite ore. If applied too freely to
land it is decidedly injurious 20 vegetation,
! but as caustic lime is not to any extent
| directly injurious to vegetation, 1t seems as
! If caustie magnesia, which is but about
one seventh as soluble, should be even less
| injurious. As an Offset to the difficulty of
| dissolving the caustic magnesia, it is much
more stable than caustic lime, which by the
/ absorption Of carbonic acid and water is
| transformed into carbonate Of lime. Caustic
magnesia, on the other hand, is first trans
formed in the hydrate, which substance is
even harder to transform into the carbon
ave YUAN CeAuSksC nSbcSl-' IL otAA4
further increase the availability OF magne-
SUM to the plant,
THE ACIDS OF THE SOIL
Unite rather with the caustic magnesia
than with the carbonate OF lime, which
already contains an acid (carbonic) which
would first have to be expelled before the
lime could recombine with any other acid.
These organic salts of magnesium are much
more soluble than the corresponding salts
of lime. Water is carried down to the
roots of plants which is saturated with
these soluble salts of magnesium, and the
roots in imbibing this water absorb, at the
same time, more magnesium than can be
made available by the plant. 1t is this
abundance OF magnesium, which exerts a
detrimental effect on the growth of
the plant 1t must not be understood
that the absence of magnesium in soils
would be desirable; on the contrary,
certain amount of that element is
absolutely necessary to the healthy
growth and development of plants.
L is only when conveyed to the roots in ex-
cessive quantities that magnesium becomes
injurious to the plant The chloride,
nitrate and sulphate of magnesium do not
need specific description. They are salts
OF magnesium formed by treating the car
Donate with ehlorhydric, nitric, or sui
phuric acid. The action of these compounds
is beneficial to vegetable growth. but owing
to the limited supply they have,
as yet not come into general use as fertil-
izers. The phosphate of magnesium exists
very generally throughout the animal body,
and is almost invariably found, though in
small quantities, in roots and soils, and to
considerable extent in the ash of many
plants and seeds. It is substance of little
economic value to the agriculturist. and as
such it will not be considered further.