Vermont farmer. [volume] (Newport, Orleans County, Vt.) 1870-1877, 1871-12-23

phate of lime, or more recently. trcalcic
Il combination of three equiv
alents of lime with one of phosphoric acid
hence the name "tribasic." three of base
with one of acid. This is the form in which
1t commonly occurs in nature 1t dissolves
in water very slowly and with difficulty, and
hence is called insolube. To convert this
INTO soluble phosphate, or as known to chem
lists, mono-phosphate of lime, or monocalcic
phosphate. it is needful to take away from
tribasic phosphate t'Co of its three equivalents
of base, Chat is to say, of limc,) leaving one
OF lime IN combination with one of phosphor-
ic acid. Combined in this proportion it is
very easily soluble. Indeed, if made dry. by
ARTIFICIAL means, 1t has such IN attraction for
water that it will take it from the air and
become wet again. This change from tri-
basic to monobasic phosphate, or from in
soluble to soluble, is effected by the agency
of sulphuric acid, which has IL stronger atln-
ity for lime than phosphoric acid has. and so
the sulphuric acid takes away lime and com
blnes with it, forming sulphatc of lime, which
Is the same thing as gypsum. We do not put
sulphuric acid with tricalcic phosphate for
the sake of making gypsum. BY no means !;
for we can get enough of this ready made
from sources in nature cheaper than we can
make it. But we do it for the sake of the
other result, viz, the conversion of insoluble
phosphate to soluble.
Thus you see that when only pure tricalcic
phosphate and sulphuric acid are put togeth-
er you have mixed result, COMPOST, con-
sisting of soluble phosphate of lime and sui
phate OF lime. Still more is the product II
compost If bone is used in place of phosphate
of lime alone; for only half of bone is phos-
phate-the rest being chiefly animal matter.
This animal matter, while decomposng in
the soil. yields ammonia from the nitrogen
1t contains, and this Is as far as possible from
being an objection, for we find that super
phosphate, the value of which consists solely
in its phosphoric acid, is only II special ma
nure, and fitted for certain crops, as turnips,
peas, clover, &C., and for soils particularly
destitute of this substance. But let it con
tain also fair proportion of ammonia or OF
nitrogen in any form useful to plants, and it
/ is adapted to many crops-Indian corn
grains generally, and vegetables generally,
and to II great majority of soils. In other
words, it is no longer a Special but more
nearly II general manure. You see also, that
the term Superphosphate is commerci;,
and not. II chemical term Formerly chem
lists used the term superphosphate to indicate
the salt now known us monOphosphate but
1t is obsolete ut present and only retained in
commerce. 1t is equally shown that Sill
perphosphate is, and necessarily must be, Il
compost mi one The Unlue of artich depeaad,
Uholly upon he skill and fiel,ty acsM whicl
suitable mdtertdtS are cO2n6lned IN Suitdblt
proportions.
Many commercial manures sold urdel
other names are simply superphosphates
such us g Ammoniated Guano," Soluble
Pacific Guano," and many others The
change of title is probably due to the odiun
attachedt to the word superphosphate in tn,
minds of many, and this in its turn is duo tt
the vast amounts of trash which have beer
palmed off for superphosphate.
II The first general remark offered regarding
the use of commercial manures is that
would never recommend their substitution
in place OF farm yard manures, nor in plac,
of any manurial resources which can be pro
cured ut home.
The first business of every farmer SHOULD
be to secure ways and means to preserve fiil
ly all the excreta of cattle, liquid and solid
, and would here remark, that the liquid por
tions are rarely sufficiently thought of. For
where some kinds of food are employed, a,
clover hay for example, OF cotton seed cake