IMPROVEMENTS IN THE MANUFACTURE OF INDIA-RUBBER
Year: 1855

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields.
in the County of Middlesex, and of Glasgow, North Britain, Gentleman,
for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF INDIA-RUBBER."
-A communication from Austin S. Day, of the United States of America.
Sealed the 30th October 1855, and dated the 7th August 1855.
PROVISIONAL. SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on the
7th August 1855.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, and of Glasgow, North Britain, Gentleman, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF INDIA-
RUBBER ," a communication from Austin S. Day, of the United States of
America, to be as follows:-
This Invention relates to a peculiar system or mode of treating caoutchouc
and other gums in a raw state, for the purpose of entirely freeing such gums
from dirt and all foreign bodies, and of removing also any obnoxious gases con-
tained therein, whereby the subsequent process of curing or vulcanizing
may be more readily and effectually carried out than when the gums are left in
a comparatively impure.state before being vulcanized. In carrying out this

page_text: Invention, the caoutchouc or other raw gums to be treated is first cut or torn
by any suitable machinery into small shreds or pieces, and is then well washed
in water in the ordinary manner, by which means the largest and heaviest of
the foreign matters are readily removed. The wash water is afterwards
allowed to drain off, and the caoutchouc or other gum is placed in an air-tight
vessel, which may be composed of boiler plates of a requisite size and strength,
according to the size of the vessel, and the pressure to which it is to be
subjected. The air and noxious gases are exhausted from the caoutchouc
or other gum by. means of an air pump, or other suitable exhausting appa-
ratus, connected with the vessel; and when a sufficient vacuum is produced
in the air-tight vessel, a solution of caustic alkali, composed of caustic soda
or potash, is admitted therein through suitable pipes and stop-cocks connected
with one or more reservoirs containing the alkali. This solution completely
impregnates the gum, and also the wood, bark, and other porous foreign
matters, which foreign matters are thereby rendered of greater specific gravity
than when they are in their natural condition, whilst at the same time they
are loosened and partially detached from the caoutchouc or other gum under
treatment. When these gums have remained a sufficient time under the
action of the caustic alkali, the solution is drawn off through a suitable
outlet pipe into a cistern, and the gum is removed from the air-tight vessel,
and placed in a vat filled with water, where it is kept well stirred and
agitated, in order to detach the particles of cut caoutchouc or other gum
from each other. As soon as this occurs, the greater specific gravity,
acquired by the foreign porous substances while subjected to the previous
action of the caustic alkali, causes them to sink to the bottom of the cistern,
whilst the pure gum is left floating on the surface. The gases and other
foreign matters being thus thoroughly removed from the gum, it is, after being
well washed and dried, ready for immediate, use or for market.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on the 3
7th February 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
and of Glasgow, North Britain, Gentleman, send greeting.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of August, in the year of our Lord
One thousand eight hundred and fifty-five, in the nineteenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said John Henry Johnson, Her special license that I, the said John Henry
Johnson, my executors; administrators, and assigns, or such others as I
the said John Henry Johnson, my executors, administrators, or 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 THE MANUFACTURE OF INDIA-RUBBER," a communication
from Austin S. Day, of the United States of America, upon the condition
(amongst others) that I; the said John Henry Johnson, by an instrument in
writing under my hand and seal, 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 I, the said John Henry Johnson, 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 accompanying Drawings, and to the
letters and figures marked thereon, that is to say :-
The said Invention relates to a peculiar system or mode of treating caout-
chouc and other similar gums in a raw state, for the purpose of entirely freeing
such gums from dirt and all foreign bodies, and of removing also therefrom
any obnoxious gases contained therein, whereby the subsequent process of
curing or vulcanizing may be more readily and effectively carried out than
when the gums are vulcanized in a comparatively impure state.
In carrying
out this Invention, the caoutchouc or other similar raw gum to be treated is
first cut or torn by any suitable machinery into sinall shreds or scraps, and
is then well washed in water in the ordinary manner, by which means the
largest and heaviest of the foreign matters are readily removed. The wash
water is afterwards allowed to drain off, and the caoutchouc or other gum is
placed in an air-tight vessel, which may be composed of boiler plates of a
requisite size and strength, according to the size of the vessel, and the pressure
to which it is to be subjected. The air and noxious gases are then exhausted

page_text: from the caoutchouc or other gum by means of an air pump, or other suitable
exhausting apparatus, connected with the vessel; and when a sufficient vacuum
is produced in this air-tight vessel, a solution of caustic alkali, composed of
caustic soda or potash, is admitted therein through suitable pipes and stop-
cocks connected with one or more reservoirs containing the alkali. This
solution completely impregnates the gum, and also the wood, bark, and other
porous foreign matters contained therein, which foreign matters are thereby
rendered of greater specific gravity than when they are in their natural
condition, whilst at the same time they are loosened and partially detached
from the caoutchouc or other gum under treatment. When these gums have
remained a sufficient length of time under the action of the caustic alkali, the
solution is drawn off through a suitable outlet pipe into a cistern below, and
the
gum is removed from the air-tight vessel, and placed in a vat filled with
water, when it is kept well stirred or agitated, in order to separate or detach
the particles of caoutchouc or other gum' from each other.. As soon as this
occurs, the greater specific gravity, acquired by the foreign porous substances
while subjected to the previous action of the caustic alkali, causes them to sink
to the bottom of the cistern, whilst the pure gum is left floating on the surface:
The gases and other foreign matters being thus thoroughly removed from the
gum, it will be ready for use after being well washed and dried.
And in order that the said Invention may be fully understood, I shall now
proceed particularly to describe the same, and for that purpose I shall refer to
the Figure on the Sheet of Drawings hereunto annexed.
The accompanying Drawing represents an arrangement of apparatus for
facilitating the treatment of caoutchouc and other similar raw gums in the
manner and for the purpose herein-before described." A is an air-tight
receiver, of a cylindrical or other suitable form, composed of boiler. plates of
sufficient strength to withstand the atmospheric pressure to which it is subjected.
in forming a vacuum therein. This receiver is hermetically closed at each end
by a spherical head or cover B, secured thereon by bolts and nuts, as shewn
in the Drawing, and is supported horizontally on the floor C by the blocks or
supports D, D, which keep it slightly elevated; from the bottom of the receiver
is conducted a drain or discharge pipe E, fitted with a strainer at. F, inside
the receiver, and passing through the floor to the cistern G.
Hand Hare.
two other cisterns, placed above the receiver A, and supported on the platform:
or framework I. These cisterns are connected with each other by the horizontal
pipe and cock J, and are each fitted with a branch pipe K, K', leading to the
receiver below; an air pump L, or other convenient exhauster of suitable size, is.

page_text: connected by the pipe M with the top of the receiver. In connection with the
lower cistern G is fitted a lift and force pump N, communicating with the upper
tanks or cisterns H, H', by a suitable supply pipe N¹.
ご
In the bottom tank or cistern G, I place a solution of caustic soda or potash,
which is then pumped into the upper tanks H, H¹, by the pump N, the 'two
stop-cocks O, O', in the branch pipes K, K', being previously closed to prevent
the solution from entering the receiver, whilst at the same time the communi-
cation is opened between the two upper tanks. The gum is now introduced
into the receiver A in quantities of from one to five thousand pounds weight,
according to the size of the apparatus, and the head B of the receiver is fitted
into its place, and firmly secured by the bolts and nuts for that purpose. The
air pump L is then put into operation, and a partial vacuum produced in
the receiver by-exhausting the air therefrom, and from the interstices of the
gum, whilst at the same time all noxious gases are drawn off or exhausted.
The two stop-cocks O, O', are now opened, and the caustic alkali flows through
the pipes K, K¹, into the receiver A, and falling on the gums contained
therein enters the cavities and fills all the interstices thereof: The wood, bark,
and other porous foreign matters are also filled with the alkali, and are: thereby
rendered of greater specific gravity than when they are in their natural state,
whilst at the same time they are loosened and partially detached from the
gum. I allow the gum to remain in the alkali until the woody and porous
substances are fully impregnated with the solution. The time required for this
part of the process depends in a great measure upon the quality of the gum,
and the quantity of the foreign matter which it, may contain. The liquor is
now drawn off from the receiver A through the discharge or drain pipe E by
opening the cock E, and allowed to run into the cistern G. When this liquor
has all run off, the head B is removed and the gum is withdrawn from the
receiver, when it is thrown into vats of suitable size containing water, in which
it is so stirred or agitated as to allow the particles of cut gum and foreign
matters to be detached or separated from each other. So soon as this occurs,
the greater specific gravity, acquired by the foreign porous substances, while
subjected to the action of the alkali, causes them to sink to the bottom of the
cistern, whilst the comparatively pure gum is left floating upon the water.
The gases and other foreign matters being thus thoroughly eradicated from the
gum, the latter is well washed and dried, and is then ready for immediate
use or for market.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried into

page_text: effect, I would observe, in conclusion, that I do not confine or restrict myself
to the precise details or arrangements which I have had occasion to describe or
refer to, as many variations may be made therefrom without deviating from
the principles or main features of the said Invention; but what I consider to
be novel and original, and therefore claim as the Invention secured to me by
the herein-before in part recited Letters Patent, is,-
First, the general construction and arrangement of apparatus for treating
cu de india-rubber and other similar gums, as herein-before described.
Second, the exhausting of the noxious gases from the crude gum, whereby
the subsequent process of vulcanization is rendered more certain & effective
in its result.
Third, the system or mode of separating the porous foreign substances
from crude gums, by impregnating such porous substances with alkaline or
other solutions having a greater specific gravity than water, and afterwards
allowing such porous substances to sink in water whilst the comparatively
pure gum floats upon the surface:
In witness whereof, I, the said John Henry Johnson; have hereunto
set my hand and seal, the Seventh day of February, One thousand
eight hundred and fifty-six.
J. HENRY JOHNSON. (L.8.)