IMPROVEMENTS IN TANNING, AND IN THE APPARATUS EMPLOYED THEREIN
Year: 1861

page_text: LETTERS PATENT to Augustin François Menard, of No. 10, Rue de
Strasbourg, in the City of Paris, in the Empire of France, for the Inven-
tion of "IMPROVEMENTS IN TANNING, AND IN THE APPARATUS EMPLOYED
THEREIN." A communication from abroad by Yves Auguste Rehm, re-
siding at Basse Yutz, Department of the Moselle, in the Empire of
France, Sugar Baker.
Sealed the 11th February 1862, and dated the 15th August 1861.
PROVISIONAL SPECIFICATION left by the said Augustin François Menard
at the Office of the Commissioners of Patents, with his Petition, on
the 15th August 1861.
I, AUGUSTIN FRANÇOIS MENARD, of No. 10, Rue de Strasbourg, in the City
of Paris, in the Empire of France, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN TANNING, AND IN THE APPARATUS EMPLOYED
THEREIN," (a communication) to be as follows:-
This Invention relates to a new and rapid system of tanning leather of every
kind, and consists, first, in the use of bark in bundles, instead of being reduced
to powder, as in the ordinary method.
Secondly, the peculiar arrangement of the apparatus to be employed. .
Thirdly, the employment of carbonic acid and other gas, whether the tanning
is performed in a vacuum by hydrostatic pressure, or by the old method.
Fourthly, the mode of operating upon the skins in the vats by the injection
of various gases combined with electric and galvanic currents, to effect the
rapid tanning of the leather.

page_text: Fifthly, placing the skins in calcareous, magnesian, aluminous, silicious, or
ferruginous solutions, in which is injected various gases in combination with
an electric and galvanic current for the formation of substances required in
tanning.
Sixthly, in the mode described for constantly preserving the strength of the
tannin solution at any temperature or condition of the atmosphere, and pre-
venting the formation of gallic acid by means of carbonic acid.
Seventhly, the application of carbonic acid and other compounds of carbon,
to form chemical compounds with the mineral substances herein-after
described.
Eighthly, in rendering leather more pliable and more impermeable to water
by the saponification of fatty matters with sulphurets of carbon.
In carrying out my Invention I form solutions of tannin of different degrees
of strength with bundles-of-oak bark-;-these-solutions-are-placed in a series of
vats, vessels, or pits arranged in parallel lines, or in any other convenient
manner. The skins are plunged in the said vats or vessels and operated upon
alternately by contact with the tanning liquid in combination with solutions
of aluminum, calcium, sodium, and other similar bodies, in which is injected
carbonic acid gas or compounds of carbon, gaseous or liquid, according to the
quality-and-use of the leather required; for the purpose of gradually coagulating
the gelatine and albumen of the skins. By the action of electricity and forcing
currents of gas into the solutions the pores of the skins become opened; and the
tanning of the leather is rapidly effected. Other barks may be employed
instead of oak bark to form solutions of tannin, and producing tannate of
gelatine under the action of carbonic acid.
For steeping and taking the hair off the skins, I adopt the following method:-
I expose the skins to the action of currents or jets of steam and gas in a
suitable vessel, which are simultaneously, brought into contact with them, and
which cause the skins to be freed from hair in more or less time according to
the nature and quality of the leather required. I dispense with the ordinary
process of passing the skins through acidulated liquor vats, and proceed at
once with the tanning after the operation of washing.
DESCRIPTION OF THE MODE OF TANNING.
I employ vats or vessels furnished with pipes, by which a communication is
formed one with the other, thus allowing the overflow of the tanning liquids
from one vat to another in a gradually diluted and weakened state; these vats
or pits are fed by a continuous stream of tanning solutions supplied from
suitable reservoirs of the extracting and macerating apparatus in which the

page_text: The
bark is placed and operated upon, and as the solutions flow from one vat to
another, they permeate the skins and carry off the gases taken up by them.
The vats or pits to the number of forty (for example) are arranged in two
series parallel to each other or in a circle or other convenient manner.
solution of tannin flows one into the other from vat No. 1 to No. 40. The
bundles of bark (or any other substance containing tannin) are put two or
three times each day into vat No. 20, whence they are taken to vat No. 19,
then to No. 18, and so on until they arrive at No. 1, after which fresh bark is
placed in No. 20, and an equal quantity of spent bark withdrawn from No. 1
the bark having remained the same length of time in each vat or vessel. The
solution of tannin having acquired its greatest density in vat No. 20 then
decreases in strength until it reaches vat No. 40, whence it flows into a
reservoir from which it is conveyed to the vats to be again strengthened with
bark. The vats No. 20 to 40 inclusive are furnished with a false bottom pierced
with holes. Between these bottoms a pipe is introduced to convey carbonic
acid gas sinto the vats for the purpose of preventing decomposition of the tannin
solutions therein and the formation of gallic acid, I establish by any suitable
and convenient means an electric or galvanic current in four vats (of the
series No. 20 to 40) containing solutions of lime, phosphate of lime, barytes,
alumina or magnesia in combination with gases to assist the action of the
tannin on the skins. The different mineral substances may be rendered acid
by an admixture of hydrochloric or nitric acid and alkaline by ammonia or
potash.
I make leather impervious to water by fixing therein grease and resin
dissolved in sulphuret of carbon
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Augustin François Menard in the Great Seal Patent Office
on the 15th February 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, AUGUSTIN
FRANÇOIS MENARD, of No. 10, Rue de Strasbourg, in the City of Paris, in the
Empire of France, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifteenth day of August, in the year of our Lord One
thousand eight hundred and sixty-one, in the twenty-fifth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me,. the said
Augustin François Ménard, Her special licence that I, the said Augustin

page_text: François Ménard, my executors, administrators, and assigns, or such others as
I, the said Augustin François Ménard, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and law-
fully 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 "IMPROVEMENTS IN TANNING, AND IN THE APPARATUS EMPLOYED
THEREIN," (a communication from Yves Auguste Rehm, a person resident a
Basse Yutz, Department of the Moselle, Empire of France, Sugar Baker,) upon
the condition (amongst others) that I, the said Augustin François Ménard, my
executors or administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and, 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 Augustin François Ménard, do hereby
declare the nature of my 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:-
This Invention relates to a new and rapid system of tanning leather of every
kind, and consists,
First, in the use of bark in bundles instead of being reduced to powder, as
in the ordinary method.
Secondly, the peculiar arrangement of the apparatus to be employed.
Thirdly, the employment of carbonic acid and other gas, whether the
tanning is performed in a vacuum, by hydrostatic pressure, or by the old
method.
Fourtlily, the mode of operating upon the skins in the vats by the injection
of various gases combined with electric and galvanic currents to effect the
rapid tanning of the leather.
Fifthly, placing the skins in calcareous, magnesian, aluminous, silicious, or
ferruginous solutions, in which is injected various gases in combination with
an electric and galvanic current, for the formation of substances required in
tanning.
Sixthly, in the mode described for constantly preserving the strength of the
tannin solution at any temperature or condition of the atmosphere and pre-
venting the formation of gallic acid by means of carbonic acid.
Seventhly, the application of carbonic acid and other compounds of carbon

page_text: to form chemical compounds with the mineral substances, herein-after
described.
Eighthly, in rendering leather more pliable and more impermeable to water
by the saponification of fatty matters with sulphurets of carbon.
In carrying out my Invention I form solutions of tannin of different degrees
of strength with bundles of oak bark. These solutions are placed in a series
of vats, vessels, or pits arranged in parallel lines or in any other convenient
manner. The skins are plunged in the said vats or vessels and operated upon
alternately by contact with the tannin liquids in combination with solutions
of aluminum, calcium, sodium, and other similar bodies, in which is injected
carbonic acid gas or compounds of carbon, gaseous or liquid, according to the
quality and use of the leather required, for the purpose of gradually coagu-
lating the gelatine and albumen of the skins. By the action of electricity
and forcing currents of gas into the solutions the pores of the skins become
opened and the tannin of the leather is rapidly effected. Other barks may
be employed instead of oak bark to form solutions of tannin and producing
tannate of gelatine under the action of carbonic acid.
For steeping and taking the hair off the skins I adopt the following method:-
I expose the skins to the action of currents or jets of steam and gas in a
suitable vessel, which are simultaneously brought into contact with them, and
which cause the skins to be freed from hair in more or less time, according to
the nature and quality of the leather required. I dispense with the ordinary
process of passing the skins through acidulated liquor vats, and proceed at
once with the tannin after the operation of washing.
DESCRIPTION OF THE MODE OF TANNING.
I employ vats or vessels furnished with pipes, by which a communication is
formed one with the other, thus allowing the overflow of the tanning liquids
from one vat to another in a gradually diluted and weakened state. These
vats or pits are fed by a continuous stream of tanning solutions supplied from
suitable reservoirs of the extracting and macerating apparatus in which the
bark is placed and operated upon; and as the solutions flow from one vat to
another they permeate the skins and carry off the gases taken up by them.
The vats or pits, to the number of forty (for example), are arranged in two
series parallel to each other, or in a circle or other convenient manner. The
solution of tannin flows, one into the other, from vat No. 1 to No. 40. The
bundles of bark (or any other substance containing tannin) are put two or
three times each day into vat No. 20, whence they are taken to vat No. 19,
then to No. 18, and so on until they arrive at No. 1, after which fresh bark is

page_text: placed in No. 20, and an equal quantity of spent bark withdrawn from No. 1,
the bark having remained the same length of time in each vat or vessel. The
solution of tannin having acquired its greatest density in vat No. 20 then
decreases in strength until it reaches vat No. 40, whence it flows into a
reservoir, from which it is conveyed to the vats to be again strengthened with
bark. The vats No. 20 to 40 inclusive, are furnished with a false bottom
pierced with holes. Between these bottoms a pipe is introduced to convey
carbonic acid gas into the vats for the purpose of preventing decomposition of
the tannin solutions therein and the formation of gallic acid. I establish, by
any suitable and convenient means, an electric or galvanic current in four vats
(of the series No. 20 to 40) containing solutions of lime, phosphate of lime,
barytes, alumina, or magnesia in combination with gases, to assist the action
of the tannin on the skins. The different mineral substances may be rendered
acid by an admixture of hydrochloric or nitric acid and alkaline by ammonia
or-potash. I make leather impervious to water by fixing therein grease and
resin dissolved in sulphuret of carbon.
.
Having now fully described and set forth the nature and object of this
Invention of "Improvements in Tanning, and in the Apparatus employed
therein," I claim as of this Invention, the improved system of tanning, sub-
stantially as herein described.
In witness whereof, I, the said Augustin François Ménard, have hereunto
set my hand and seal, this Fifteenth day of February, in the year of
our Lord One thousand eight hundred and sixty-two.
A. F. MENARD. (L.S.)