CERTAIN IMPROVEMENTS IN THE MANUFACTURE AND APPLICATION OF LEATHER AND CERTAIN VEGETABLE SUBSTANCES, TO BE USED IN COMBINATION WITH LEATHER, INDIA RUBBER, CANVAS, SILK, COTTON, WOOL, AND OTHER FIBROUS SUBSTANCES, IN THE MANUFACTURE OF CERTAIN WATERPROOF ARTICLES
Year: 1849

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
CHARLES CLARKSON, of 31, Bennett Street, Stamford Street, in the County of
Surrey, Manufacturer, send greeting.
WHEREAS by Royal Letters Patent under the Great Seal of Great Britain
and Ireland, bearing date at Westminster, the Eighth day of February, in the
twelvth year of the reign of Her present most Excellent Majesty Queen
Victoria, Her said Majesty did give and grant unto me, the said Thomas
Charles Clarkson, my exors, adñors, and assigns, Her especial license, full
power, sole privilege and authority, that I, the said Thomas Charles Clarkson,
my exors, adñiors, and assigns, and such other as I, the said Thomas Charles
Clarkson, my exors, adñors, and assigns, should at any time agree with, and
no others, should and lawfully might make, use, exercise, and vend, within
that part of Her said Majesty's United. Kingdom of Great Britain and
Ireland called England, Her Dominion of Wales, and Town of Berwick-
upon-Tweed, and in the Islands of Jersey, Guernsey, Alderney, Sark, and
Man, and in all Her Majesty's Colonies and Plantations abroad, my Invention
of "CERTAIN IMPROVEMENTS IN THE MANUFACTURE AND APPLICATION OF LEATHER
AND CERTAIN VEGETABLE SUBSTANCES, TO BE USED IN COMBINATION WITH LEATHER,
INDIA RUBBER, CANVAS, SILK, COTTON, WOOL, AND OTHER FIBROUS SUBSTANCES,
IN THE MANUFACTURE OF CERTAIN WATERPROOF ARTICLES;" in which said Letters
Patent is contained a proviso obliging me, the said Thomas Charles Clarkson,
to cause a particular description of the nature of my Invention, and in

page_text: what manner the same is to be performed, under my hand and seal, to be
enrolled in Her said Majesty's High Court of Chancery within six calendar
months from the date of the said Letters Patent.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Thomas Charles Clarkson, do hereby declare that the nature of my said
Invention, and in what manner the same is to be performed, are fully described
and ascertained by the following description thereof, that is to say :-
My Invention relates,―
First to improvements in the manufacture of leather by which the various
parts of a hide are rendered of a more equal and uniform character than by
the processes hitherto adopted.
Secondly, to a peculiar mode of applying leather in the formation of mill
bands or straps, and-also-for-harness purposes.
Thirdly, to a peculiar mode of combining leather with vegetable substances.
with or without canvas, silk, cotton, or othe fibrous materials, and also a
peculiar mode of combining vegetable substances with canvas, silk, cotton, or
other fibrous material, such combination being suitable as a material for the
manufacture of various articles.
With reference to the first part of my Invention, which relates to the
process of tanning, or the conversion of hides into leather, I take the hides,
after having been separated from the hair and other superfluous matters, and
cut them up into sections, at which stage I select the various parts of the
hide and arrange them for the several purposes for which they may be best
adapted. I then split or cut the hides or parts of the hides so as to render
them of a uniform thickness, or for the purpose of reducing them in thickness,
after which they are to be subjected to the several processes as follows:-
In order to preserve the animal gelatine of the hide in the leather, I first
subject the hides to a solution of chloride of sodium and alumina of a strength
regulated as circumstances may require. In this solution they are to be
thoroughly saturated. The hides, or sections of hides, are afterwards to be
immersed in an alkali in order to remove to a certain extent the solution
adhering to the bide, by which removal it will be in a state of preparation
to undergo the process of tanning. During the immersion of the "hide" (I
use the term "hide" as meaning either an entire hide or hides, or parts of
such) in the solution of chloride of sodium and alumina, I remove it two,
three, or more times, and subject it to the process of stretching similar to the
stretching to which leather is usually subjected after tanning.
The ordinary process of stretching is productive of injury to the fibres of
the leather in the thinner and weaker parts from the inordinate tension which

page_text: is applied to it, although the thicker and stronger parts may remain wholly
unaffected thereby; and moreover the tension to which leather is usually
subjected in stretching does not remove all the expansibility therefrom, as
when in use for various purposes it will still continue to expand, whereas,
according to my improvement, by subjecting the hide to stretching from time
to time while in a green state, or during its conversion into leather, the whole
stretch is effectually removed, and this without the application of such force
as will injure or deteriorate the quality of the article when manufactured.
The hide after having been immersed in the alkali, with the animal gelatine
preserved as before stated, is in a state preparatory to undergo the process
of tanning, which I conduct in the following manner :-Instead of plunging
the hides indiscriminately into the tan-pit as usual, I suspend each hide or
piece of hide by one edge, so as to extend and expose its whole surface in the
tan-pit placing them at such distances apart as to permit the free access of
the tannin solution between each. While the hide is so suspended I run
the tanning solution into the pit so as to cover the whole. The tan-pits are
so constructed as to permit the solution to escape at the bottom, while at the
same time a fresh supply is admitted at the top, by which means I am enabled
to keep up or even to increase the strength of the solution. During the
immersion of the hides I prefer that the solution first introduced should be
of medium strength, and gradually change the liquid as described, and at the
same time keeping or increasing it to the strength required. By thus exposing
both surfaces of the hide to the action of the tannin solution, it becomes
uniformly acted upon throughout, and by regulating the duration of immersion
I am enabled to pass the tannin properties entirely thro' the hide, or simply
to tan the surface, which will be impregnated to a greater or less depth
according to the time it remains in the pit. By this mode of tanning I am
enabled to coat the exterior surface of a hide uniformly and similar to all
outward appearance and usefulness to ordinary tanned leather, while the interior
has the animal gelatine preserved, which therefore retains all the tenacity of what
is commonly known as "tawed leather," by which it is greatly increased in
durability for many purposes, in which state it may be so applied. This mode
of conducting the operation of tanning is also extremely beneficial where the
hide is to be thoroughly tanned, by enabling the workman to determine the
exact time to which the hide should be subjected to the action of the tanin to
effect that object. Whereas, according to the ordinary method, some parts of
the same hide will be thoroughly tanned, while others remain scarcely affected
thereby; consequently the continued immersion necessary to complete the
tanning of those parts of the hide untanned most injuriously affects these parts

page_text: previously converted into leather, by destroying the remaining natural pro-
perties of the material. Another advantage in this mode of tanning is, that
the whole process is rendered of much less duration, and requires less attention
and handling on the part of the workman, as the necessary supply of fresh
liquid, and the escape of the spent or partially spent liquid at the bottom
of the pit may be so regulated as to maintain the necessary change without
any attention, merely noting the duration of time the hides are to continue
immersed in the pit, which, as before mentioned, will be regulated according
to the depth to which the hides are to be impregnated with the solution by
which they are either partially or wholly converted into tanned leather.
During the process of tanning, I repeat the operations of stretching from time
to time as in the subsequent process described.
With regard to the second part of my Invention, it relates to a peculiar
mode of constructing mill bands or straps, which consists in employing the
parts of hides best adapted for the purpose, which have been selected as before
mentioned in a preliminary stage, and during the process of tanning, and which
have been split and tanned as described. I then proceed to cut those parts
of the hide into strips of a suitable width. In order to produce a strap of a
permanent and enduring character I place two or more layers of the leather
together, taking care that different parts of the hide come together, such as the
shoulder to the "butt," which renders the whole of a uniform strength. In
combining two or more thicknesses of leather for this purpose I introduce a
thickness of cork, by which an elasticity is imparted to the strap in the direc-
tion of its thickness as to cause it to adhere to a "rigger," and retain tight
hold without creating any undue friction on the bearings of such rigger. I
sometimes also introduce one or more thicknesses of cotton cloth or other
fibrous material between the layers of leather and cork, in order to render it
of increased tenacity. I connect the different layers of leather, or layers of
leather and other materials, with some adhesive cement, such as marine glue,
or a solution or sheet of india rubber; and as a further connection they may
be pegged in the well-known manner of pegging boots, which last process
may be executed so as to render the same of an ornamental character. In
connecting these layers I also observe to connect the continued lengths in such
manner as to effect what is understood by breaking joint with the other
thickness or thicknesses of leather, the ends of the continued lengths
being united by bevilling and pegging, or rivetting the same together. I
pass the straps between a pair of rollers, or otherwise subject them to
pressure so as to ensure contact and adhesiveness between the several
thicknesses of material by which the whole are firmly united, and rendered
.

page_text: of nearly a uniform thickness. In connecting the several layers of
material in the manufacture of mill straps I wind them round a drum of a
suitable diameter, in order that a sufficient allowance shall be made for the
difference in length which ought to exist between the outer and inner layers of
straps, so as to cause the several thicknesses of leather of which it may be
composed to take an equal proportion of the strain to which the whole strap
may be subjected. In the introduction of the cork layer I prefer that it should
not be exposed at the edges of the strap, but so narrowed and thinned at the
edges as to permit the layers of leather to come in contact with each other, or
with the layers of cotton or other woven fibrous material employed. By thus
forming the strap it will be rendered slightly convex, causing it to bind firmest
in the middle, producing the elasticity before mentioned, and thereby giving it
increased hold. This mode of combining layers of leather is also applicable
to the manufacture of harness and other straps subjected to any degree of
tension.
Third part of my Invention, which relates to the peculiar combination of
vegetable substances with leather, and also silk, cotton, wool, or other fibrous
material, or with fibrous materials only. The improvement consists in the
cementing alternate thicknesses of two, three, or more of these materials, the
combination being adapted for each particular purpose to which the material is
to be applied, cork being the vegetable material I use in all cases, which is
prepared in sheets of a thickness suitable for each individual purpose, but
seldom exceeding one eighth of an inch, and in some cases as thin as a sheet of
writing paper. In forming articles if for building purposes, such as in houses,
for the framework or other parts of railway and other carriages, I employ
sheets of cork, which I alternate with layers of wood. and cotton, or other
fibrous material, cementing the whole firmly together with marine glue, a
solution of india rubber, or other suitable adhesive matters, so as to retain the
whole firmly together. In carrying out any particular construction according
to this part of my Invention, I proceed by first shaping a layer or thickness of
wood to the purpose required, and afterwards applying alternate layers of cork
and cotton or other woven fabric till the required substance is obtained, which
is afterwards dressed and finished off in the ordinary manner. In such cases,
where it is desirable to render the combination extremely tenacious and slightly
pliant, I introduce layers of leather instead of some, or the whole, of the layers
of wood, but which will be determined in all cases according to circumstance.
Where it is designed for the construction of roofs or other positions where
arching may be necessary, I prefer to cement the alternate layers transversely
to their length, aul building it up on a centre, so as to assume the form required

page_text: as in the ordinary mode of throwing an arch or span of masonry. But this may
also be readily effected in layers in the direction of its length by bending the
first layer to the required form and then annexing the other layers in the
manner before described. This method of combining cork in layers is also
extremely applicable as a buffing medium for railway carriages; in which case
I alternate the layers of cork with layers of cotton cloth, or other woven
fabric, the layers being disposed transversely to the direction of the strain from
the buffer rod or head, and being interposed between the rod or head and
the carriage as usual to receive the shocks produced by concussion, the
layers of material are compressed into closer contact without permitting
any lateral spread, the layers of cork being retained of their original diameter
or superfices by the alternate layers of woven fabric. Cork so applied
-possesses sufficient compressibility and elasticity to form a good recipient of
the force arising from concussion-in- railway carriages, having this advantage
over the buffers hitherto employed, that the reaction or return of the elastic
material to its original position is slow and unproductive of the injurious
results arising from the sudden reaction of the buffers hitherto used.
I also apply a similar combination of cork and cotton cloth, or other woven
fabric as a packing for joints in pipes and other like objects; and in case of the
pipes being subjected to steam or other heat the cork should be introduced in
layers of not more than one sixteenth of an inch, as it is liable to char if
placed in a body. Washers are cut from this material, and interposed between
the ends of pipes or in similar positions, and used as an ordinary packing.
This mode of combining cork in layers is also applicable for the purpose of
making hose pipe or tubing, which 1 effect by wrapping sheets of cork round
an iron tube, forming a triblet, and alternating the layers of cork with leather,
cotton, cloth, or other fibrous material, using at the same time a solution of
india rubber or other cement, causing the several surfaces to adhere firmly
together. For greater ficilities in connecting the several layers it is of
advantage to introduce a heating medium into the triblet, by which the adhe-
sion is more readily and completely effected. The alternate layers should be so
disposed that the points of union or joints should in no case be in conjuction.
By thus disposing the cork in layers any continuity of the pores is prevented,
besides which they are filled by the cement used, producing a material
thoroughly impervious to moisture, and also extremely pliable and enduring
in its character, rendering it highly qualified for that purpose.
The coating of wires for telegraph and other purposes is conducted in a very
similar manner to the forming of tubing, the cork sheeting being wrapped round
in alternate layers with some woven fabric, and caused to adhere in close contact

page_text: as before by some adhesive matter. Where two or more wires are to be
combined, the layers of cork and woven fabric are introduced between them so
as to perfectly insulate each individual wire. The whole covering then
receives a coating of marine glue as a preservative for the whole. Wires
thus covered are thoroughly protected from the wet or damp, from the imper-
vious nature of the combination and its enduring character as a covering.
In the manufacture of hats and caps I employ one or more layers of cork to
form the body, which for this purpose is cut extremely thin if more than one
layer is employed. In proceeding to form a hat body-I use the term "hat
body" in expressing that part of a hat between the brim and the tip-I coat
the layer of cork with a solution of india rubber, and apply thereto a thin
woven fabric on the side intended for the interior of the hat, passing the
combined layers through rollers, or by other pressure causing them to adhere
in close contact. I then place a fabric on the block on which the hat is to be
forined, causing it to fit closely thereto. This fabric is previously saturated with
a solution of india rubber. This saturation forms an adhesive surface on which to
form the cork body. By preference I apply the cork as previously prepared in
two pieces on to the block, and unite them at the sides of the hat, the joints
running in a vertical direction from the brim to the tip. It is not essentially
necessary that the junction should be in a vertical direction so long as it
passes from the brim to the tip. In applying the cork fabric to the block, or
to the saturated covering on the block, I cause the two pieces to adhere in a
vertical line at the back and front parts of the block, from which point it is
gradually compressed to the surface of the block so as to produce a smooth
surface. The india rubber solution causes the cork material to adhere to the
block as the work progresses. Having carried the cork material on one
side up to the point of union all surplus material is removed, and the edge
bevelled off preparatory to the forming the joint with the other piece. The
other piece of material is then similarly pressed up to the block, and an union
effected between the pieces of cork material by lapping the second piece over
the previously levelled edges, and causing them to adhere by means of a
solution of india rubber, after which the superfluous edges of the second piece
of material are removed. By thus gathering the cork material up to the
block and causing it to adhere thereto as the work progresses, I am enabled to
carry out and remove the surplus material at those points of the circumference
of the hat body which are of the lesser diameter, and this being removed and
the joint formed while the cork material is in close contact with the block, the
hat body is thereby caused permanently to retain the configuration so imparted.
1 now remove the hat body from the block (the block being formed in pieces

page_text: as usual for that purpose; and if it is desired to render it as light as possible
I remove the fabric from the interior of the hat body which was used in retain-
ing it to the form of the block, and substitute a net or other lining required.
Hat bodies so manufactured are then tipped, covered, and otherwise finished in
the usual way. By using a solution of india rubber, I obtain just that amount
of adhesion necessary to cause the cork to adhere throughout on coming in
contact with the fabric on the block, by which the smooth and even surface is
obtained, while at the same time the adhesive matter remains in such state
that the adhering surfaces can be readily separated when required for the
subsequent operations. This mode of combining cork in layers with leather
or with woven fabrics or fibrous materials, is also applicable for a variety of
other purposes, such as the formation of buckets instead of leather, or
for boats, barrels, parts of boots and shoes, flooring, railway sleepers, lining,
covering, or forming other parts of railway or other carriages, male and female
wearing apparel, boxes, bags, table covers, hat linings, pavement, bottles, or
water-tight receptacles, army accoutrements, marquecs, book backs, and.
floating dresses; the combination of either or all of the substances mentioned
with the layers of cork, depending upon the circumstances of each individual
case which regulates the character of the article to be produced, and whether
soft and pliant or of a more rigid nature, the amount of tenacity being ensured
by a due proportion of fibrous material calculated to produce such effect.
Having thus described the nature of my Invention, I would have it under-
stood that what I claim, and desire to be secured by the said before in part
recited Letters Patent 'is,―
First, the mode of tanning leather, in which the hide is suspended in the
pits, and subjected to the action of a gradually charging liquid, as described,
and also the partial tanning of hides as described.
Secondly, the combining thin or split hides in layers, placing the "butt" to
the shoulder part of the hide instead of employing thick substances of leather,
as hitherto, in the manufacture of straps for driving bands or harness as
described. I also claim uniting the thicknesses of leather for a driving band
or strap, while encircling a drum or other surface for the purpose herein
described.
Thirdly, the combining cork, wood, india rubber, and other vegetable sub-
stances in alternato layers, with leather or with fibrous materials, such as
cotton, silk, canvas, or wool, and causing the several layers to adhere to each
other by a solution of india rubber, marine glue, or other suitable cement, so
as to produce a waterproof material, applicable for and in the manufacture of
the various articles mentioned in the manner herein-before described.

page_text: Fourthly, combining a layer or layers of cork, and a layer or layers of
tarlatan, or other woven fibrous material, with a solution of india rubber in
the formation of hat bodies, and also the application of a solution of india
rubber to the manufacture of hat bodies of cork, for the purpose of retaining
them in shape during and after their formation.
In witness whereof, I, the said Thomas Charles Clarkson, have hereunto
set my hand and seal, this Eighth day of August, in the year of our
Lord One thousand eight hundred and forty-nine.
AND BE IT REMEMBERED, that on the Eighth day of August, in the
year of our Lord 1849, the aforesaid Thomas Charles Clarkson came before
our said Lady the Queen in Her Chancery, and acknowledged the Specifi-
cation aforesaid, and all and every thing therein contained and specified, in
form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute made for that purpose.
Enrolled the Eighth day of August, in the year of our Lord One thousand