IMPROVEMENTS IN TANNING HIDES OR SKINS AND IN APPARATUS TO BE USED THEREFOR
Year: 1871

page_text: LETTERS PATENT to Bristow Hunt, of No. 1, Serlo Street, Lincoln's
Inn, in the County of Middlesex, Gentleman, for the Invention of
“IMPROVEMENTS IN TANNING HIDES OR SKINS AND IN APPARATUS TO BE USED
THEREFOR." -A communication from abroad by William Alfred
Hacker, of Lynn, in the County of Essex, State of Massachusetts,
United States of America.
PROVISIONAL SPECIFICATION left by the said Bristow Hunt at the
Office of the Commissioners of Patents, with his Petition, on the
15th August 1871.
I, BRISTOW HUNT, of No. 1, Serle Street, Lincoln's Inn, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN TANNING HIDES OR SKINS AND IN APPARATUS
TO BE USED THEREFOB," (a communication to me from abroad by William
Alfred Hacker, of Lynn, in the County of Essex, State of Massachusetts,
United States of America,) to be as follows:-
This Invention relates to improvements in the method of tanning
skins, and consists partly in tanning the same by an improved method,

page_text: which is designated or to be known as "the racking and vacuum
art of tanning," and partly in improved apparatus for carrying the same
into practical effect, which apparatus may also be employed in liming
and bating them.
The apparatus consists of a vat similar to an ordinary tan vat of t
convenient capacity to hold the liquid to be used in the process, whether
it be for depilating or tanning the skins, immediately over which, or in
close proximity thereto, is placed a hollow air-tight drum or vessel,
provided at one end with an opening and a closing cap or door, such
opening being for the introduction of the skins or hides (to be operated 1
upon) into the drum or vessel, or its internal chamber. Within this
vessel is placed one or more racks or other equivalent means of suspending
the hides or skins. A pipe is connected from the interior of the drum
to an exhaust pump capable of extracting from the drum or vessel the
air which it may contain at the time, a vacuum gauge being provided :
for determining the proper degree of exhaustion in the drum.
Pipes or conduits extend over the drum and open into its ends, and
other pipes open out of these pipes and lead down and open into the
drum at its bottom. From both of the latter pipes a branch pipe leads
down into the tank or vat, and these pipes both above and below where
the said branch pipe is joined are provided with stop-cocks. At the
bottom of the drum is also a discharging conduit or pipe likewise
provided with a stop-cock. A vertical glass pipe communicates at its
ends by pipes with the upper and lower parts of the cylinder or drum,
and serves to indicate at any time the height of the liquid when in such
drum. The last-mentioned stop-cock is closed while the drum is being
exhausted of air and opened only when it may be desirable to withdraw
from the drum its liquid contents. By means of the branch pipe and
the two pipes to which it is attached liquid from the vat may bo drawn
into the drum and be discharged oither into the lower or upper part
thereof as circumstances may require.
The operation of this improved apparatus differs from that of others
for a similar purpose in the following particulars :-The skins are
suspended in the drum or chamber upon a rack or racks, and instead of
pumping into the drum the liquid for the treatment of the skins, the
air (after the door of the drum is closed) is first to be exhausted from
the drum and its contents, the vacuum gauge affording a ready means
of determining the exact degree of exhaustion of the air, which operation

page_text: opens tho pores of the skins to better advantage, for it prepares them
for receiving the liquor better than can be done after they have been
immersed in the liquid. Furthermore while the skins are immersed the
degree of rarefication of the air can be determined at any time. The
degree of exhaustion (for the most beneficial results) should be about
fourteen pounds to the inch, and it should be as steadily maintained as
possible while the skins are being treated.
After the exhaustion of the air one or more of the cocks belonging to
the two pipes to which the branch pipe above mentioned is attached aro
opened, when the liquid in the vat will, under the atmospheric pressure,
be forced into theso distributing pipes, and through them into the drum,
and be thrown in various directions upon the skins, thereby facilitating
their absorption of it, and bringing about the consequent speedy and
proper tanning of the hides or skins.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Bristow Hunt in the Great Scal Patent Office on
the 14th February 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BRISTOW
HUNT, of No. 1, Serle Street, Lincoln's Inn, in the County of Middlesex,
Gentleman, 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 seventy-one, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Bristow Hunt, Her special licence that
I, the said Bristow Hunt, my executors, administrators, and assigns, or
such others as I, the said Bristow Hunt, 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 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 HIDES OR
Skins and IN APPARATUS TO BE USED THEREFOB," (a communication to me from
abroad by William Alfred Hacker, of Lynn, in the County of Essex, State
of Massachusetts, United States of America,) upon the condition (amongst

page_text: others) that I, the said Bristow Hunt, my exccutors 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 6
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Bristow Hunt, do hereby declaro
the nature of the said Invention, and in what manner the samo is to be
performed, to be particularly described and ascertained in and by the 1
following statement in writing, and on reference being had to the
accompanying Sheet of Drawings, that is to say :-
This Invention relates to improvements in the method and means of
tanning hides or skins, and consists partly in tanning the same by an
improved method designated the "racking and vacuum art of tanning," 1
and partly in improved apparatus for carrying the same into practical
effect as herein-after described, which improved method and means may
also be employed in depilating, liming, and bating them.
The Invention will be readily understood on reference being had to
the accompanying Sheet of Drawings, and to the following description 2
and explanation thereof, that is to say :—
. On the accompanying Sheet of Drawings Figure 1 represents an end
elevation, Figure 2 a plan view, Figure 3 a transverse section (through
about the line a, b, Figure 2, and looking in the direction of the arrow c),
and Figure 4 a longitudinal vertical section of the improved apparatus. 2
The apparatus consists of a vat 1 (similar in construction to an
ordinary tan vat) of convenient capacity to hold the liquid to be used
in the process (whether it be for depilating, tanning, liming, or bating
the skins); immediately over which, or in close proximity thereto, is
placed a hollow air-tight drum or vessel 2, provided at one end with an 3
opening (and a closing cap or door 3) for the introduction therein of the
skins or hides to be operated upon. Within the vessel 2 is placed one or
more racks 4 or öther equivalent means by which the hides or skins can
be suspended. A pipe 5 is in connection at one end with the interior of
the vessel 2, and at its other end with an exhaust pump capable of 3
extracting from the vessel 2 the air which it may at any time contain,
the degree of exhaustion being regulated and ascertained by means of a

page_text: vacuum gauge 6 in connection with the interior of the vessel. 7,7,
represent pipes or conduits extending the length of the vessel 2, and
opening into the top of its ends; out of these open other pipes 8, 8, which
lead down and open into the vessel at its bottom. In connection with
both of the pipes 8, 8, is a branch pipe 9, which leads down to near the
bottom of the tank or vat 1, and by means of which liquid from the vat
may be drawn into the vessel. The pipes 8, 8, both above and below
where the pipe 9 joins them, are provided with stop-cocks, 10, 10, 11, 11.
At the bottom of the vessel 2 is a discharging conduit or pipe 12, like-
> wise provided with a stop-cock 13, which is closed when the vessel is
being exhausted of air as herein-after described, and opened only when
it may be desired to withdraw from the vessel its liquid contents. 14
represents a vertical glass pipe or tube which communicates at its ends
by pipes 15 with the top and bottom of the vessel 2, and serves to
indicate at any time the height of liquid when in the vessel.
The mode of operation of this improved apparatus differs from that of
others for a similar purpose in the following particulars :-
In the first place, the skins or hides are suspended in the tanning
vessel 2 upon a rack or racks, or their equivalents.
Secondly. Instead of pumping into the vessel the liquid for the
treatment of the skins it is forced in by the pressure of the external
air.
And, thirdly. The air (after the stop-cocks 10, 11, and 13, and the door of
the vessel 2 are closed) is exhausted from the vessel and its contents (tho
vacuum gauge 6 affording a ready means of determining the exact and
proper degree of exhaustion), which operation opens the pores of the
skins, and so prepares them for receiving or being moro thoroughly
saturated or treated with the liquor better than can be done after
they have been immersed therein. The degree of exhaustion (for the
most beneficial results) should be about 14 pounds to the inch, and
should be as steadily maintained thereat as possible while the skins are
being treated, and during that time the degree of rarefaction of the air
can be determined at any time. ·
After the exhaustion of the air one or more of the cocks 10, 11, is (or
are) opened, when the liquid in the vat 1 will, under the atmospheric
pressure, be forced into their respective distributing pipes 7, 8, and into
the vessel 2, and be injected therein at the top or bottom, as circum-

page_text: stances may require, and in various directions upon the skins, the
previous exhaustion of the containing air facilitating their absorption of
it, and bringing about the consequent speedy and proper tanning,
depilating, liming, or bating of the skins or hides.
Having now described the nature and object of the said Invention for
"Improvements in Tanning Hides or Skins and in Apparatus to be used
therefor," together with the manner in which the same is to be or may
be performed or carried into practical effect, I would remark in con-
clusion that I claim as the Invention (communicated to mo by the
above-named William Alfred Hacker),―
Firstly. The general arrangement and combination of the improved
mcans and apparatus substantially as above described, and as illustrated
on the accompanying Sheet of Drawings, for the purposes herein set
forth, or any mere variation thereof.
And, secondly. The new or improved method or process heroin
described when used alone or in combination with the same, which
improved method consists essentially in the suspension of the skins or
hides to be operated upon within the vessel upon a rack or racks, or
their equivalents, and afterwards exhausting the chamber and its
contents of most, if not all, of the air contained therein; and subse-
quently introducing the tanning or other liquid into the space so
exhausted of air, by which improved method the skins or hides are more
speedily and thoroughly acted upon.
In witness whereof, I, the said Bristow Hunt, have hereunto set my
hand and seal, this Fourteenth day of February, in the year of
night hundred and sozont