The Abbeville banner. [volume] (Abbeville, S.C.) 1847-1869, 1847-08-18
TANNING LEATHER.

TANNING LEATHER.
Leather is composed of gelatine or glue
and albumen, with quantity Of oleaginous
matter composed Of ealine and stearine.-
by mixing lime, or any alkali, with the
soap, or steara,e oflilne, and BY boiling and
acid is the principle which preserves the
hide and renders it leather, and it is con-
tanned in oak bark in greater proportions
than in other things, and is separated from
it more easily. The effect of tannic acid is
10 coag ui;,ie aud render insoiubie the ge-
latino upon which it acts as an astringent,
and contacts its PARTICLES The object then
oflaying the hide in the bark liquor is to
render insc lIble the gelatine, and also to add
as much weight as possible. 1t used to take
years of soaking 10 bring the acid into con-
tact with the ultimate PARTICLES of the hide,
butn now it is done by chemical means in
very short time. Magnesa nc cutralizes the
acid, and hence water containing magnesia,
which is the case with Newark water, Is
injurious to the liquor.
Several machines have been invented
for fastening the process Of bringing the
acid in contact with the ultimate particles.
One of them consisted in passing the skin
between rollo!s, which press ont the weak
liquor and allow it to receive the strong g.
Another was to fasten the hide to the peri
phery Of a wheel revolving in the vat. by
which it is lifted from and immersed in the
liquor frequently. Three or four vats pIa-
ccd side by side, were also used, in which
the leather is suspended upon frames which
are keptin motion. None ofthese methods,
however, were considered as perfectly sue
ccssful, An Englishman attracted much
attention some time ago with cylinder, in
which he placed the hides and liquor, and
keptit constantly revolving, and in thisma
ner he tanned the leather in about 40 days.
In tanneries where the leather has the great
est weight. they have the liquor of certain
strength, and change it every day. Hides
are in this way tanned in about four months
which is better and more rapid than the old
method of letting them lie in weak liquor.
The operation of the rollers was to disintre-
gate the leather and do away with some of
the PARTICLES, and thus injured it. Some in
ventors place the hides under an airpump
with the liquor. and then exhaust the air,
and upon letting it in again the external
pressure forces the liquor into the hide by
repeating the process and finishing by for
cling the liquor in with a force pump the
leatheris speedily tanned. English leather
thus tanned was much more durable than
the American leather, and it had been fin
ished in month.
Prof Mapes stated before the Newark
Conversational Meeting that he had been
experimenting some time upon this subject
and hit upon plan which he thought was
worthy the consideration Of practical men.
1t was to prepare a cylinder with holes per-
forated throughout its circumference and
spread the hides over these, upon the inside
and then pour in the liquor. Ifthe cylin.
der be reyolved about 5000 times in a mi
mute the water will pass through, by the
centrifugal force rapidly as if nothing re-
strained it, and by actual experiment he
found that no tannic acid was left in the
liquor that thus came through the leather.
He thought with regard to the English lea
ther. tanned IN a vacuum, that arsenic had
had been possibly put in by the tanner, as
portion had upon analysis been found in it,
and it was we'll known that this was great
preservative,
HINTS TO FARMERs.-Tomato make
excellent preserves.
Toads are the very best protection Of cab
bage against lice. e.. = 3. 4ts .....'
. Plan.s, when droo oping, are revived by a
few fyrpi mo- lnf r. 3 =, y,l,1,y :. =