IMPROVEMENTS IN TANNING, AND IN THE PREPARATION OF EXTRACTS TO BE USED THEREIN
Year: 1865

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in
-
the County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS
IN TANNING, AND IN THE PREPARATION OF EXTRACTS TO BE USED THEREIN."
A communication from abroad by Emanuel Desiré Coëz, of Paris, in
the Empire of France, Chemist.
Sealed the 80th January 1866, and dated the 80th August 1865.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with his Petition, on the
30th August 1865.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN TANNING, AND IN THE PREPARATION OF EXTRACTS TO BE USED
THEREIN," a communication to me from abroad by Emanuel Desiré Coëz, of
Paris, in the Empire of France, Chemist, to be as follows:-.
This Invention relates to an improved system or mode of tanning-skins,
whereby the duration of the process is greatly reduced, whilst at the same
time greater suppleness and pliability are imparted to the leather; also to the
preparation of extracts to be employed in the process above referred to. -
According to this Invention it is proposed to tan hides and skins-by-the-
employment of pure extracts of tannin obtained from tan, sumac, and more
particularly from what is known as dividivi or the fruit of the Brazil wood
tree, which is known also as Lima wood or sapin wood. These extracts are

page_text: used of various degrees of strength or concentration, but in preparing the
extract of dividivi, which in all cases I prefer by reason of the good qualities
it imparts to the leather, I first prepare an aqueous solution thereof, which I
filter thoroughly in order to remove all useless and injurious substances there-
from; I then concentrate this filtered solution to 30° Beaumé. The effect of
this extract thus obtained is very regular, inasmuch as it is not impeded in its
action by any impurities contained therein, and it is to this purity that is due
also the promptitude of the process. It is simply requisite to dissolve the
extract in boiling water in order to thoroughly divide the molecules and then
to use it in the process of tanning at the ordinary temperature. By this
process I obtain in about eight days leather which, under the ordinary system
of tanning, would require six months to prepare. One part by weight of the
prepared extract of dividivi is equivalent to four parts by weight of ground
tan.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on the
28th February 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fieids, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the 30th day of August, in the year of our Lord One
thousand eight hundred and sixty-five, in the 29th year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said John
Henry Johnson, Her special license that I, the said John Henry Johnson,
my executors, administrators, and assigns, or such others as I, the said
John Henry Johnson, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for " IMPROVE-
MENTS IN. TANNING, AND IN THE PREPARATION OF EXTRACTS TO BE USED THEREIN,"
a communication to me from abroad by Emanuel Desiré Coëz, of Paris, in
the Empire of France, Chemist, upon the condition (amongst others) that I,
the said John Henry Johnson, my executors or administrators, by an instru-
ment in writing under my hand and seal, should particularly describe and.

page_text: ascertain the nature of the said Invention, and in what manner the same was
to be performed, and cause the same to be filed in the Great Seal Patent
Office within six calendar months next and immediately after the date of the
said Letters Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement, that is to say:-
I
The said Invention relates to an improved system or mode of tanning skins,
whereby the duration of the process is greatly reduced, whilst at the same
time greater suppleness and pliability are imparted to the leather; also to the
preparation of extracts to be employed in the process above referred to.
According to this Invention it is proposed to tan hides and skins by the
employment of pure extracts of tannin obtained from tan, sumac, and more
particularly from what is known as dividivi or the fruit of the Brazil wood
tree, which is known also as Lima wood or sapin wood. These extracts are
used of various degrees of strength or concentration, but in preparing the
extract of dividivi, which in all cases I prefer by reason of the good qualities
it imparts to the leather, -I- first prepare an aqueous solution thereof, which I
filter thoroughly in order to remove all useless and injurious substances there-
from; I then concentrate this filtered solution to 30° Beaumé. The effect of
this extract thus obtained is very regular, inasmuch as it is not impeded in its
action by any impurities contained therein, and it is to this purity that is due
also the shortness of the process. It is simply requisite to dissolve the extract
in boiling water in order to thoroughly divide the molecules, and then to use
it in the process of tanning at the ordinary temperature. By this process
I obtain in about eight days leather which, under the ordinary system of
tanning, would require six months to prepare. One part by weight of the
prepared extract of dividivi is equivalent to four parts by weight of ground
tan.
I employ by preference the following process for preparing the extract of
dividivi: I treat one part of natural dividivi with eight parts of boiling
water, and the liquor, after cooling and settling for eight days, is then decanted
off and filtered. The deposit, when removed, supplies a liquor charged with
useful principles which may be subsequently used for treating a fresh mass.
The washing water which is used for cleansing the filters should be mixed
with the liquor intended to be concentrated, which I prefer generally to carry
up to a strength of 30° Beaumé.
The improved preparations herein-before described may be used in the

page_text: ordinary process of tanning with a view to accelerating the process, and the
quantities of such extracts, as well as their strength and time of action, may
be varied according to circumstances.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe in conclusion that what I consider to be novel
and original, and therefore claim as the Invention secured to me by the
herein-before in part recited Letters Patent is,-
First, the preparation of the extract of dividivi and its application and use
to and in the tanning of hides and skins, substantially as herein-before
described.
Second, the application and use to and in the tanning of hides and skins of
pure extracts of tannin prepared substantially as herein-before described.
In witness whereof, I, the said John Henry Johnson, have hereunto set
my hand and seal, this Twenty-eighth day of February, One thousand
eight hundred and sixty-six.
J. HENRY JOHNSON.
L.S.)