CERTAIN NEW AND IMPROVED PROCESSES OF TANNING
Year: 1836

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FRANCIS
BREWIN, of the Old Kent Road, in the County of Surrey, Tanner, send
greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eleventh day of January, in the sixth year of His reign,
did, for Himself, His heirs and successors, give and grant unto me, the
said Francis Brewin, His especial licence, full power, sole privilege and
authority, that I, the said Francis Brewin, my exors, admors, and assigns,
or such others as I, the said Francis Brewin, my exors, admors, or assigns,
should at any time agree with, and no others, from time to time and
at all times during the term of years therein expressed, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town
of Berwick-upon-Tweed, my Invention of "CERTAIN NEW AND IMPROVED
PROCESSES OF TANNING;" in which said Letters Patent is contained a proviso
that I, the said Francis Brewin, shall cause a particular description of the
nature of my Invention, and the manner in which the same is to be
performed, to be inrolled in His said Majesty's High Court of Chancery within
six calendar months next and immediately after the date of the said in part
recited Letters Patent, as in and by the same, reference being thereunto had,
will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Francis Brewin, do hereby declare that the nature of my said Invention
consists in the making or preparing a new liquor or liquors for tanning or
manufacturing raw hides and skins into leather, and for retanning leather
manufactured in the ordinary way, from certain exotic substances which have
not heretofore been in use for manufacturing leather in this country, or from
a combination of these substances with other materials already in common
use, by means of which new liquor or liquors leather can be manufactured of
a superior quality in less time than usual and at much less expence, and by
which also leather manufactured in the ordinary way may be improved in
quality. And I declaro that the manner in which the said Invention is to be
performed is fully shewn and set forth in the following description thereof (that
is to say):-
:-
I employ in the making and preparing of the said new tanning and
retanning liquor or liquors, certain substances known in English commerce by
the names of gum kino, divi divi, and terra japonica, all of which I find
contain much larger proportions of tannen than the best English oak bark, and
yield liquors possessed respectively of the following properties:-A solution
of gum kino imparts to leather a brownish red colour, but improves it
considerably in point of closeness and firmness of texture; a solution of
divi divi gives a very light color to leather; a solution of terra japonica of the
sort generally imported in small square pieces, gives a dull light colour; and
one of terra japonica of the sort generally imported in large cakes, a brownish
red, similar to that obtained from gum kino. A solution of divi divi I prepare
in the same way as the ordinary bark liquors are made in vats or lecks by
tanners; but gum kino and terra japonica require to be treated in the manner
following if the gum kino is in large peces, or if the terra japonica is of the
sort which is sold in large cakes, I first break these large pieces and cakes
with a hammer into small pieces; I then steep the whole far about three days
in cold water or cold weak tan liquor, after which I put the whole into what
I call a rubbing tub, of the construction shewn in the Drawing in the margin
hereof, for the purpose of being still farther reduced, or I use hot water, or
hot weak tan liquor, in which case I put the whole of the materials at once
into the rubbing tub, and leave them to steep for about an hour only; which
last process is that which I prefer. This tub (a) is about five feet deep and
four feet wide in every part, and has a loose cover (6) just so much smaller
to it in circumference, that when not kept up by the materials in the tub,
it will readily fall to the projection or stopper (e) fixed at about four inches
from the bottom, and in this cover, on the under part thereof, about

page_text: one hundred spikes of copper, wood, or any other material that will
not stain the liquor, of about three inches long, are firmly inserted.
A square wooden shaft (c) about five inches thick, with a wheel or handle (d)
at top to turn it by, is passed through an orifice of corresponding size and
description in the centre of the cover (6) and drops into a recess in the bottom
of the tub large enough to allow the shaft to turn freely within it. The
materials having stood sufficiently long for steeping, the shaft of the tub is
worked round by manual or other power, which carries around with it the
loose cover with the spikes underneath, till by the stirring and rubbing action
of the spikes the pieces of the gum kino or terra japonica in the tub are either
successively dissolved or reduced to such small dimensions as to pass easily.
between the cover and the sides of the tub. And in order that the said
cover may press continually downwards on the materials in the tub, and.
descend as the materials become dissolved or reduced to the dimensions afore-
said, a heavy weight or weights is or are placed and kept on the top thereof.
during the whole of the operation. And in preparing the said solutions for
use I employ more or less water or weak tan liquor, according to the sort of.
leather which is intended to be manufactured (that is to say), for sole leather I
use about fifty to one hundred pounds of the gum kino or of the divi divi or of
the terra japonica, with about one hundred gallons of water or weak tan liquor;
and for manufacturing dressing leather I use, with every fifty to one hundred
pounds of the divi divi and light terra japonica, about three hundred gallons
of water or weak tan liquor, rarely using the gum kino or dark terra japonica
at all in the manufacture of dressing leather, or any sort of leather, in respect
to which colour is an object; or instead of at once dissolving the said materials
in the said proportional quantities of water or tan liquor I dissolve them at
first in any smaller quantities of water or weak tan liquor, and afterwards
reduce the solutions to the required strength by the addition of water or weak
tanning liquor. And when I have, by the processes aforesaid, obtained. tlic..
requisite solutions of gum kino, divi divi, light terra japonica, and dark
terra japonica, I generally mix for sole leather the different solutions together.
in a common tan vat in the following proportions, that is to say, one quarter.
of the solution of gum kino, one quarter of the solution of divi divi, one eighth.
of the solution of the dark terra japonica, and three eighths of the solution
of light-coloured terra japonica. I then put into the liquor so prepared and
compounded about one fourth more raw hides or skins than would in general
be put by tanners into an equal quantity of bark liquor, and with every hide I
put on an average about one pound of oak bark, in the same way as tanners
now use bark in the vats with hides and skins. For manufacturing dressing

page_text: leather I mix the solutions of divi divi and light terra japonica prepared as
before mentioned, and put the hides or skins into them with the same pro-
portions of bark and liquor as are herein-before directed to be used in the case
of sole leather. When the leather is required to be of a very close and firm
texture, and the colour is a matter comparatively unimportant, I make use of a
larger proportion of the liquor of gum kino than is before directed; and when
the dark terra japonica is low in price, and when the colour to be given to the
article is immaterial, I also make use of a larger quantity of that material
than of any of the others; and when it is desired to have the leather of a colour
lighter than that which results from the combination of all the four liquors
in the proportions before recommended, I diminish the proportional quan-
tities of the dark colouring substances, according to the particular shade of
colour required to be given to the article. And whereas some one or
more of the said articles may occasionally be so scarce in the market
or so high in price that it may be practicable or economical to employ it
or them in the quantities before recommended with the other substances, I
declare that the use of any one or more of the said substances may be
dispensed with either wholly or partially, but subject to the following modi-
fications in the effects produced, that is to say, if gum kino be used alone, the
leather produced will be too hard and close for general purposes; if divi divi be
used alone, it will produce leather lighter in colour than usual; if terra japonica
be used alone, an article will be produced possessed neither of that firmness
nor that color which is generally desirable in leather, while by the addition of
divi divi to gum kino or terra japonica a better article is produced than can
be obtained from either gum kino or terra japonica separately. And whereas
also the prices of all the four articles aforesaid may at times rise so high, that,
notwithstanding their superior tanning properties, they cannot with economy
be entirely substituted for oak bark or any of the other barks or tanning mate-
rials now in common use, I declare that the same may be advantageously used
in combination with the said common materials in the proportions following,
that is to say any given quantity of gum kino, divi divi, and terra japonica,
mixed in the proportions before recommended, may be combined with any
quantity of oak bark; or any given quantity composed of six twelfth parts of
light terra japonica, four twelfth parts of divi divi, and two twelfth parts of
gum kino may be combined with an equal quantity of mimosa bark or kermac
root; or any given quantity composed of gum kino, divi divi, and terra japonica,
in equal proportions, may be combined with two eighth parts of valonia, and
two eighth parts of oak bark; or lastly, eighth parts of gum kino, divi divi, and
terra japonica may be combined with two eighth parts of oak bark, and one

page_text: eighth part of shumach. When gum kino, or divi divi, or terra japonica, or
any of them are intended to be used along with oak or other bark, they may
either be ground very small in a common bark mill, after being well dried if
not sufficiently dry for grinding in their original state, and then mixed up
with the bark. Or, the bark and divi divi may be steeped by themselves in
the taps, and the liquor drawn off and made hot, and then put in such
quantity into the rubbing tub as is necessary to dissolve the gum kino or terra
japonica, as before described, which latter method is that which I prefer; or
water or weak tan liquor alono, either hot or cold, may be used to dissolve the
new materials before mixing them with the common liquors. The liquors made
from these various articles, I prefer using of about the same, tanning strength
as those made from the new materials alone. And though the proportions in
which I have herein-before directed the gum kino, divi divi, and terra japonica
to be mixed with each other, or with oak bark, and others of the materials
already in common use, are those which I have found to answer best under
ordinary circumstances, I declare that the said proportions may be varied at
the discretion of the practical tanner, according as the taste of customers in
respect to the colour of leather may vary, or according to any particular
quality desired to be given to the manufactured article, or according to the
comparative cost at different times of the different materials. And I declare
that for retanning or improving leather made in the ordinary way, I put it into
a fresh liquor, the same as is herein-before directed to be used for sole leather,
and after it has remained therein for one day, I handle it; I then allow it to
remain in the liquor for from eight to fourteen days, after which I take it
out and dry it, and if necessary restrike it.
And I declare that what I claim as my Invention is the making and
preparing of a tanning liquor or liquors for tanning or for manufacturing
raw hides and skins into leather, and for retanning leather manufacture<l
in the ordinary way with gum kino, divi divi, and terra japonica, either
employed separately or combined with each other, or with other substances
already in common use in the different proportions, and in the manner herein-
before specified or in any other proportions and manner which a change of
circumstances may render more suitable.
And such my Invention being, to the best of my knowledge and belief,
never heretofore used in this country, I do hereby declare this to be my
Specification of the same. And that I do verily believe this my said Speci-
fication doth comply in all respects, fully and without reserve or disguise,
with the proviso in the said herein-before in part recited Letters Patent

page_text: Inrolled the Eleventh day of July, in the year of our Lord One
thousand eight hundred and thirty-six.