IMPROVEMENTS IN TANNING, AND IN APPARATUS EMPLOYED THEREIN."
Year: 1863

page_text: LETTERS PATENT to Henry Hamer, of Kender Street, Old Kent Road,
in the County of Surrey, for the Invention of "IMPROVEMENTS IN
TANNING, AND IN APPARATUS EMPLOYED THEREIN."
PROVISIONAL SPECIFICATION left by the said Henry Hamer at the
Office of the Commissioners of Patents, with his Petition, on the
31st March 1863.
I, HENRY HAMER, of Kender Street, Old Kent Road, in the County of
Surrey, do hereby declare the nature of the Invention for "IMPROVEMENTS IN
TANNING, AND IN APPARATUS EMPLOYED THEREIN," to be as follows:-
This Invention has for its object improvements in tanning, and in apparatus
employed therein. The tanning hides and skins by the ordinary process of
steeping in open tanks occupies a great deal of time. It has been proposed
to accelerate the operation by forcing in the tanning liquor by hydraulic
pressure, but hides or skins thus tanned are considerably lighter than they
would be if tanned by the old method, consequently there is little or nothing
gained by tauning in this manuer. It has also been proposed to exhaust the
tank in which the hides or skins and the tanning liquor are placed, so as to
open the pores of the hides or skins to allow the tanning liquor to enter; and
this process is advantageous to a certain extent, but the tanning liquor is

page_text: liable to separate and become more dense at the bottom of the vessel than at
the top, so that the tanning action is irregular, besides which, the film of
liquor in immediate contact with the hides or skins becomes spent, and being
only slowly replaced by other liquor it retards the action.
According to my Invention 1 suspend the hides or skins within an air-tight
vessel, so that the tanning liquor which the vessel contains may come in
contact with every part of each hide or skin. I exhaust the air from the
tank, and further I keep the tanning liquor in motion during the process, so
as to prevent it separating, and so that it may sweep off from the hides or
skins the film of spent liquor immediately it is formed. The apparatus I
prefer to employ for this purpose is a rectangular wooden tank, capable of
being closed air-tight by a lid; within this tank is a frame somewhat shorter
than the tank, and capable of moving to and fro endwise within it, this
motion being given to it by a rod which is attached to the frame; the rod
passes out through a stuffing box in the end of the tank, and is then connected
with an excentric or other similar instrument. The frame runs backwards
and forwards within the tank on suitable guide rails, and the hides or skins
are hung on laths at the upper part of the frame transversely of the length of
the tank; as the hides or skins move to and fro the tanning liquor presses
first on one side of them and then on the other. The tank is connected with
an air pump, and is exhausted during the process.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Henry Hamer in the Great Seal Patent Office on the
28th September 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY S
HAMER, of Kender Street, Old Kent Road, in the County of Surrey, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of March, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of s
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Henry Hamer, Her special licence that I, the said Henry
Hamer, my exccutors, administrators, and assigns, or such others as I,
the said Henry IIamer, 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 lawfully

page_text: might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Inven-
tion for "IMPROVEMENTS IN TANNING, AND IN APPARATUS EMPLOYED THEREIN,"
upon the condition (amongst others) that I, the said Henry Hamer, 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 tho 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 Henry Hamer, 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 thereof, that is to say :-
.
This Invention has for its object improvements in tanning, and in apparatus
employed therein. The tanning hides and skins by the ordinary process of
steeping in open tanks occupies a great deal of time. It has been proposed
to accelerate the operation by forcing in the tanning liquor by bydraulic
pressure, but hides or skins thus tanned are considerably lighter than they
would be if tanned by the old method, consequently there is little or nothing
gained by tanning in this manner. It has also been proposed to exhaust the
tank in which the hides or skins and the tanning liquor are placed, so as to
open the pores of the hides or skins to allow the tanning liquor to enter; and
this process is advantageous to a certain extent, but the tanning liquor is
liable to separate and become more dense at the bottom of the vessel than at
the top, so that the tanning action is irregular, besides which the film of
liquor in immediate contact with the hides or skins becomes spent, and being
only slowly replaced by other liquor it retards the action.
According to my Invention I suspend the hides or skins within an air-tight
vessel, so that the tanning liquor which the vessel contains may come in
contact with every part of each hide or skin. I exhaust the air from the tank,
and further I keep the tanning liquor in motion during the process, so as to
prevent it separating, and so that it may sweep off from the hides or skins the
film of spent liquor immediately it is formed. The apparatus I prefer to
employ for this purpose is a rectangular wooden tank capable of being closed
air-tight by a lid; within this tank is a frame somewhat shorter than the tank,
and capable of moving to and fro endwise within it, this motion being given to
it by a rod, which is attached to the frame; the rod passes out through a
stuffing box in the end of the tank, and is then connected with an excentric

page_text: As the
or other similar instrument. The frame runs backwards and forwards within
the tank on suitable guide rails, and the hides or skins are hung on laths at
the upper part of the frame transversely of the length of the tank.
hides or skins move to and fro the tanning liquor presses first on one side of
them and then on the other. The tank is connected with an air pump, and is
exhausted during the process.
Having thus stated the nature of my said Invention, I will proceed moro
fully to describe the manner of performing the same.
I construct strong tanks by preference of wood, or internally lined with
wood of a strength sufficient to bear the requisite pressures. If the tanks be
of wood, then they are to be coated with asphalte or other suitable material to
render the wood impermeable to air or tanning liquor when subjected to the
pressures employed in the process. The tanks are by preference constructed
of a rectangular form, and of dimensions depending on the quantity of hides or
skins to be treated at one time. The interior dimensions, which I believe to
be most convenient are five feet six inches wide, five fect eight inches long,
and six feet two inches deep. Each tank is by preference made with a cover
of wood, or lined with wood capable of being closed air and water tight. At
the bottom of each tank a pair of parallel rails are fixed to receive and guide
the flanged wheels of a frame or carriage, which is placed within the tank.
The frame is by preference of wood of a rectangular form, mounted on two
pairs of wheels. This frame or carriage is made as open as may be at the
sides, ends, and bottom, in order that the tanning liquor in the tank may get
freely in all directions. For this purpose it is preferred that the frame should
consist of four uprights at the angles, combined together by a rectangular
frame at the top and another at the bottom. The bottom and the two sides of
the frame or carriage may also be strengthened by diagonal bars or framing.
I would, however, state that the frame or carriage may be put together in any
convenient manner. At the top of the carriage or frame there is formed a
grating of parallel laths or bars on which the hides or skins are hung, two
hides or skins connected at one of their ends being in each case hung over a
lath or bar. This carriage or frame is somewhat less in length than the tank
in which it is placed, in order that it may be moved to and fro a distance of
from eight to twelve inches within the tank; the width of the carriage is
nearly the same as the internal width of the tank, there being, however,
sufficient clearance between the sides of the carriage and of the tank to admit
of the carriage moving freely within the tank. The carriage may be moved
to and fro within the tank in any convenient manner, but I prefer that a rod
should be attached to one end of the carriage, and pass through a suitable

page_text: stuffing box at one end of the tank, and that a to-and-fro motion should be
given to such rod and to the carriage by an excentric. By these means each
frame or carriage will have a large number of hides or skins suspended within
the tank, such hides or skins being parallel to each other and to the ends of
the tank. It is preferred that several tanks should be arranged near together,
and that they should be connected by pipes and cocks in such manner that the
tanning liquor used should be capable of being run or discharged from one
tank into another.
The mode of working is as follows:-Supposing hides or skins have been
suspended on the laths of the frame or carriage, the lid or cover of the tank is
to be closed air tight; the air is then exhausted from the interior of the tank.
In practice I have used an exhaustion equal to about 13 lbs. of a vacuum
gauge, but this may be varied. A cock on a pipe connecting this tank to
another tank or to a vessel containing tanning liquor is then to be opened so
as to allow the tanning liquor to flow into the vacuum tank, or when passing
tanning liquor from one tank in which it has for a time been in use acting on
hides or skins therein. I quicken the process of transferring the tanning
liquor from one tank to another by forcing air into the tank which is to be
emptied, so that such tank becomes quickly filled with air when the cock
between it and the other tank is to be closed. I then continue to force air
into the tank till the pressure of air therein is raised to some pounds on the
square inch, so as to press the tanning liquor from the hides or skins, and I
keep up this pressure for some minutes. A pressure of five or six or more
pounds to the square inch may thus be usefully employed to press out the
tanning liquor from the wet skins or hides. The compressed air is then
allowed to escape, and the tank is then again to be made vacuous; it is then
again to be filled with tanning liquor, as above described, either from another
tank or from a vessel containing tanning liquor. When a tank has been filled
with tanning liquor the air pump or exhausting apparatus is to be worked so
as to maintain the state of exhaustion desired, and the carriage with the hi-les
or skins are to be moved slowly to and fro within the tank, by which the parts
of the hides or skins will be constantly changing their position in respect to
the tanning liquor, so that the same tanning liquor will be prevented
remaining quietly in contact with the same part of a hide or skin. By these
means the hides or skins being suspended in the vessel are not only subjected
to the action of vacuum, but they and the tanning liquor are kept in motion,
so that the liquor is prevented from separating, and as soon as a film of spent
liquor is formed on the hides or skins it is swept off them, at the same time

page_text: convenience is afforded for drawing off and again supplying the tanning liquor,
and also for subjecting the wet hides or skins to air pressure.
In witness whereof, I, the said Henry Hamer, have hereunto set my
hand and seal, this Twenty-sixth day of September, in the year of our
Lord One thousand eight hundred and sixty-three.
HENRY HAMER. (L.S.)