IM. PROV ROVEMENTS IN CLEANING OR SEPARATING GUTTA PERCHA FROM EXTRANEOUS MATTERS, AND IN APPARATUS FOR THE SAME
Year: 1860

page_text: LETTERS PATENT to William Clark, of 53, Chancery Lane, in the County
of Middlesex, Engineer and Patent Agent, for the Invention of "IM.
PROV
ROVEMENTS IN CLEANING OR SEPARATING GUTTA PERCHA FROM EXTRANEOUS
MATTERS, AND IN APPARATUS FOR THE SAME." - A communication from
abroad by Messrs. Louis Boulet, Auguste Sarazin, and Louis Hamy, of
Calais, in the Empire of France, Merchants.
Sealed the 27th March 1861, and dated the 8th October 1860.
PROVISIONAL SPECIFICATION left by the said William Clark at the
Office of the Commissioners of Patents, with his Petition, on the 8th
October 1860:
I WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex,
Engineer and, Patent Agent, do hereby declare the nature of the said Inven-
tion for IMPROVEMENTS IN CLEANING OR SEPARATING GUTTA PERCHA FROM
EXTRANEOUS. MATTERS, AND IN APPARATUS FOR THE SAME," to be as follows:-
This Invention relates to the separation of gutta percha from extraneous
matters with which it is combined, and consists, first, of apparatus whereby
gutta perchais operated on, consisting of upright shafts mounted parallel to
each other in a suitable chamber or vessel, each shaft having radial prongs or
arms which interlock with each other by the rotation of the shafts. Into this
apparatus introduce ths gutta percha to be operated upon, a sufficient
Price Sd

page_text: quantity of water being also placed in the vessel, which is heated by a steam
pipe or jet of steam entering therein. The gutta percha becomes plastic, and
is worked up by the action of the machine; but in order to its disintegration
I mix with the water a quantity of soda with a small proportion of lime to
form a lye, marking a strength of about one degree Baumé. By this means
the disintegration of the gutta percha is such that extraneous matters separate
from it, and fall to the bottom or otherwise, while the pure gutta percha rises
to the top. Space is provided at bottom to receive the deposited matters.
The gutta percha may be afterwards similarly washed in clean water. Gutta
percha so treated is clean and ready for use.
Other machines may be adopted, such as that known as the devilling
machine or masticator, which to a certain extent will answer the purpose if
the gutta percha operated on is at the time immersed in a lye, as before
described, which constitutes the principal part of this Invention.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Willian Clark in the Great Seal Patent Office on the
6th April 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, T, WILLIAM
CLARK, of 53, Chancery Lane, in the County of Middlesex, Engineer and
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of October, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said William Clark, Her special licence that I, the said William Clark.
my executors, administrators, and assigns, or such others as I, the said
William Clark, 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 Ire-
land, the Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN CLEANING OR SEPARATING GUTTA PERCHA FROM EXTRANEOUS MATTERS &
IN APPARATUS FOR THE SAME," a communication from Messrs. Louis Boulet,
Auguste Sarazin, & Louis Hamy, of Calais, in the Empire of France, Mer-
chants, upon the condition (amongst others) that I, the said William Clark,
my executors or administrators, by an instrument in writing under my, or

page_text: 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 1, the said William Clark, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say):-
This Invention relates to the separation of guita percha from extraneous
matters with which it is combined, by subjecting it to mechanical apparatus,
whereby the gutta percha is operated on, & heating the gutta percha during
its being so operated upon with a quantity of water of suitable temperature,
containing a quantity of alkali, by preference soda, with a proportion of lime,
so as to form an alkaline solution, marking a strength of, say, about half a
degree Beaumé.
By this means the disintegration of the gutta percha is
such, that the extraneous matters separate from it, and fall to the bottom, or
deposit in the water, while the pure gutta percha rises to the top. Space is
provided at bottom to receive the deposited or separated extraneous matters.
The gutta percha may be afterwards similarly washed in clean water.
Gutta percha so treated is clean and ready for use.
Such being the nature of my Inventiou, I will proceed to describe, by
reference to the accompanying Drawings, the manner in which the saune is
ents a
apparatus for operating on gutta percha to effect its cleaning according to this
Invention, and Fig. 2 a plan of the same.
a, a, is a vessel of cast iron or other suitable material, in which two, or it
may be other number of vertical shafts b, b, are disposed. These are fitted in
bearings c, c, formed in or fixed to the bridge-piece & placed across the top of
the vessel a. This bridge-piece d is securely bolted at each end to the flanges
of vessel, and supports bearings e, e, e, in which a horizontal shaft is fitted.
This shaft has mitre wheels g, g, fixed thereon, which gear into like wheels
h, h, fixed on the upright shafts b, b, as seen, and so as to impart thereto
rotary motion in opposite directions. On the shafts b, b, are securely fixed
several radial arms i, i, which are disposed so as to overlap or interlock with

page_text: each other, but without contact. It will be observed, that the upper arms i
are about the same level, or a little above the level of the water, while the
lowest one is a considerable distance from the bottom, the reason for which is,
that the gutta percha floats at or near the surface, and is beaten up by the
arms, while there is space left below, which is comparatively undisturbed, in
which the extraneous matters deposit. Suitable covers h, k, are fitted to the
flange of vessel ", to enclose it while the operation progresses. I is a steam
pipe, by which steam is admitted to the contents of the vessel, the steam
escaping by perforations at the lower part, as shown. Instead of admitting
steam to the vessel, the contents may be caused to boil by a circulation of
steam in a coil of pipes or otherwise. The steam pipe is, of course, furnished
with a suitable stop-cock to regulate the supply of steam. The shaft is
driven by a strap m, and rigger n, or by gearing, and by any suitable power.
Supposing the machine suitable for operating on about one hundredweight
of gutta percha, I place in the vessel a about one hundred and twenty gallons
of water, and cause it to boil, and then introduce about a gallon of lye prepared
from an alkali, by preference, soda and quick lime, of a strength of about
twenty degrees Beaumé. I then introduce the rough gutta percha, either in
large pieces as imported, or previously cut into smaller picces, sufficient time
being in either case allowed for the gutta percha to be come soft before putting
the machine in action. The contents of the machine are kept in a boiling
state and the machine in action for half-an-hour or an hour, according to the
original state of the gutta percha. At first it is driven about seventy or
eighty revolutions per minute, but the speed may be increased in proportion
as the gutta percha becomes comminuted. Ultimately it is thoroughly dis-
integrated, so that the particles of dirt and extraneous matters separate
from the gutta percha, and fall to the bottom of vessel a, or are absorbed by
the liquid in the vessel. The grosser part of the extraneous matters contained
in the gutta percha being thus separated, I remove the gutta percha from
vessel a, by skimming from the surface of the water, or other convenient
means, and introduce it into another similar machine, or it may be the same
machine, and treat it in the same manner in cleaner water, holding in solution
a like proportion of the lye, and so on three or four times, according to the
state of purity to which it is desired to reduce the gutta percha. Ultimately
it is washed in like manner in clean water to remove any trace of the alkaline
solution. The gutta percha may then be kneaded, masticated, or rolled into
sheets, or otherwise worked, as usual in the manufacture of gutta percha.
The lye I make use of is such as used in the manufacture of soap, and I find
that forty pounds of white soda of commerce, marking about fifty-two degrees

page_text: of the alkalimeter, with twenty pounds of quick lime in solution, forming
twenty gallons of lye, which will mark a strength of about twenty degrees
Beaume's hydrometer, when reduced by water to about a half degree Beaumé,
as above mentioned, is well adapted for my purpose.
Instead of conducting the operation of separating the gutta percha from
the extraneous matters at a heat of two hundred and twelve degrees, it
may be placed in a close vessel, and a pressure of steam generated
therein, which will produce a higher temperature if desired, and instead
of the vessel a being circular it may be oval, as seen in plan at Fig. 3, or of
other convenient form or arrangement, & the number of radial beating
arms increased, if desired.
Having now described the nature of my Invention, and in what manner
the same is to be performed, I hereby declare that I claim, as the Invention
intended to be secured by the said Letters Patent,---
First, the treating gutta percha with a heated alkaline solution as above
described.
Secondly, apparatus constructed and arranged for the purpose of treating
gutta percha as above described.
In witness whereof, I, the said William Clark, have hereunto set my
hand and seal, this Sixth day of April, in the year of our Lord, One
thousand eight hundred & sixty-one.
Witness,
W. G. E. SwINNOOK,
53, Chancery Lane.
W. CLARK. (L.S.)