THE IMPROVEMENTS IN TANNING BY MACHINERY AND CHEMICALS
Year: 1856

page_text: LETTERS PATENT to Alexander Ebenezer Riddle, of 33, Walbrook, City,
and Isaac Hoare Boyd, of 3, Mansion House Place, City, for the
Invention of "THE IMPROVEMENTS IN TANNING BY MACHINERY AND
CHEMICALS." A communication from George Fenner Kendall.
Sealed the 4th November 1856, and dated the 8th May 1856.
PROVISIONAL SPECIFICATION left by the said Alexander Ebenezer
Riddle and Isaac Hoare Boyd at the Office of the Commissioners of
Patents, with their Petition, on the 8th May 1856.
We, ALEXANDER EBENEZER RIDDLE, 33, Walbrook, City, and ISAAC HOARE
BOYD, of 3, Mansion House Place, City, do hereby declare the nature of the
said Invention for THE IMPROVEMENTS IN TANNING BY MACHINERY AND CHEMICALS,
being a communication from George Fenner Kendall; a foreigner residing
abroad, to be as follows:-
The Invention consists of a false circular bottom placed in a pit, and upon-
the pit is to be placed a wheel with paddles, which when turned causes the
skins in the pit to revolve in the liquor, thereby considerably accelerating their
progress.
We claim the use of soda ash in connexion with lime and sulphate of
potash for the purpose of unhairing, and the use of sulphate of potash in the
tan liquor.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alexander Ebenezer Riddle and Isaac Hoare Boyd in the
Great Seal Patent Office on the 7th. November 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ALEXANDER
EBENEZER RIDDLE, of 33, Walbrook, City, and ISAAC HOAR BOYD, of
3, Mansion House. Place, City, send greeting..
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of May, in the year of our Lord One
thousand eight hundred and fifty-six, in the nineteenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto us, the said
Alexander Ebenezer Riddle and Isaac Hoar Boyd, Her special licence that
we, the said Alexander Ebenezer Riddle and Isaac Hoar Boyd, our executors,
administrators, and assigns, or such others as we, the said Alexander Ebenezer
Riddle and, Isaac Hoar Boyd, our, 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 THE
IMPROVEMENTS IN TANNING BY MACHINERY AND CHEMICALS, (a communication
from George Fenner Kendall; upon the condition" (amongst others) that we,
the said Alexander Ebenezer Riddle and Isaac Hoar Boyd, by an instrument
in. writing under,.our, or their, or one of their hands and seals, should par-
ticularly 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 we, the said Riddle and Boyd, do, hereby, declare the
nature of our said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following: statement,
and accompanying Drawing
By the process in ordinary-use the tanning, of skins and hides, occupy several
weeks for the smaller, and thinner kinds, and several months for the larger and
thicker descriptions; and the tanning liquor or liquid in which they are immersed
usually consists of a saturated solution of; bark, varying in strength according
to the stage of the process; such solution or extract of bark being, contained
in pits, into which the skins or hides are thrown, and is from time to time,
removed by pumping out, or is strengthened by adding thereto more tanning
bark; and the skins are also taken out from time to time and examined, and

page_text: in such cases are stacked by the side of the pit and allowed to drain off; they
are then re-immersed and the absorption of the tanning permitted again 'to go
on-untill finally the-skins are, after several weeks or several months; as the
case-may-be, tanned throughout..
Now, our Invention has for its object the more rapid performance of the
same operation, and in an equally perfect manner, and consists of treating the
hides or skins as described in the Provisional Specification of this Invention!
The mode-of-treating the hides or skins according to our Invention consists
in passing them more frequently through the tanning liquor, or causing the
tanning liquor and the hides or skins to move or circulate in the pit by means
of a paddle wheel-like drum erected over the pit, and which is caused to revolve
or rotate by hand or other power. Over a pit, four feet six inches long and three
feet-wide-we-place a drum with close ends; about three feet diaineter and of a
length sufficient to work between the sides or, in the width of the pit; the float
boards may be about seven inches in depth and of the length of the drum, 'and'
by immersing the periphery of the drum, say about eight inches below the
surface of: the..tanning liquor, we find that on communicating a slow motion,
say about twenty-four revolutions per niinute, the skins are kept in motion,
being caused to rise; from the false bottom of the pit on the one side to the
top, and are then turned over and descend again to the bottom, where each
skin in its turn again rises, and the entire number of the hides or skins are thus
caused to circulate and thereby become more readily acted upon by the tanning.
principle of the liquor or liquid in which they are-immersed... In square
bottomed pits we place a curved false bottom of open: lath work, of suitable
size and form to suit the size of the pit and the diameter of the paddle wheel-
like drum erected over it. We prefer to close each pit with a close fitting
cover, which, being hinged, may be thrown back when fresh skins have to be
put in, or those in process of tanning require to be.removed...
In the accompanying Drawing, Fig. 1 is a sectional elevation of a small tannery
according to this Invention. Fig. 2 is a plan of Fig. 1. Figs. 3 and 4 are
enlarged views of a small tan pit, fitted with the false bottom, the drum wheel,
and the close cover. The number and arrangement of the pits and gearing is
shewn with a view to convey a general idea of a small tannery, conducted under
cover of a galvanized iron shed and protected from the weather, and is not
intended to fix, limit, or confine us to the details thereof, as any other arrange-
ment or disposition of the pits may be made; but Figs. 3 and 4 illustrate the
mechanical features of our Invention; A being the pit; B, the curved false
bottom; C, the cover; D, the drum, of which a, a, are the ends; b, b, are the
float boards; c, the centre shaft or axle; d, the plummer blocks or bearings.

page_text: The drum is constructed of wood, and may be driven by a crank handle, or
by a rigger or pulley. The speed we have found suited to ordinary cases is,
when the periphery of the drum revolves, at about 200 or 220 feet per minute.
Having now described our Invention, and illustrated it by the accompanying
Drawing, we wish it to be understood that we do not claim the use of revolving
drums, wherein the tanning liquor and the hides or skins are placed and caused
to revolve together; nor do we claim any other form or kind of drum or wheel
unless it be immersed in the tanning liquor, and for the purpose of causing a
motion or circulation of the tanning liquor and skins together; neither do we
claim the use of any chemical ingredient for facilitating the absorption or
taking up of the tannin contained in the tauning liquor. But what we do
claim is the apparatus, as described, or its mechanical equivalents for effecting
a circulation of the tanning liquor or liquid and the skins, whereby the period
required or necessary for thoroughly tanning hides or skins and converting
them into leather is materially shortened, and the consequent economy effected
thereby...
In witness whereof, I, the said Alexander Ebenezer Riddle, on behalf of
myself and Isaac Hoar Boyd, have hereunto set my hand and seal, this
Thirtieth day of October, in the year of our Lord One thousand eight
hundred and fifty-six.
Witness,
ALEXANDER EBENEZER RIDDLE. (L.s.)
WILLIAM SMITH, C.E.,
10, Salisbury St.