IMPROVE- MENTS IN THE MANUFACTURE OF BLEACHING POWDER, AND APPARATUS EMPLOYED THEREIN
Year: 1860

page_text: LETTERS PATENT to Robert Calvert Clapham, of Walker, in the County
of Northumberland, Analytical Chemist, for the Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF BLEACHING POWDER, AND APPARATUS
EMPLOYED THEREIN."
Sealed the 8th March 1861, and dated the 11th September 1860.
PROVISIONAL SPECIFICATION left by the said Robert Calvert Clapham
at the Office of the Commissioners of Patents, with his Petition, on the
11th September 1860.
I, ROBERT CALVERT CLAPHAM, of. Walker, in the County of Northumber-
land, Analytical Chemist, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF BLEACHING POWDER, AND APPARATUS
EMPLOYED THEREIN," to be as follows:-
My Invention consists of a method of obtaining from a given weight of
common salt a larger quantity of muriatic acid of a strength suitable for
making bleaching powder than is obtained by the methods now commonly
used. In condensing muriatic acid from the decomposition of common salt,
a large part of the muriatic acid has hitherto been found to be of too low a
strength to be applicable to the decomposition of manganese in making
bleaching powder, and the object of the present Invention is to render the
above-named weak acid, which usually varies in strength from 1° to 6° Twaddle

page_text: commercially useful for the above object. I first cool the weak acid solutions
as they usually run from the last or weak condensers used in condensing
muriatic acid in any suitable apparatus, and then pass it down what are called
No. 1 condensers, or the strong acid condensers commonly used when decom-
posing common salt in the place of water, or it may be mixed with water; or
I expose the said weak solutions to a stream of weak or waste muriatic acid
gas till it arrives at the required strength, and in either case I then find it of
sufficient strength to use in the manufacture of bleaching powder, which
increases the produce and cheapens the cost of production of this article. The
apparatus employed resembles in principle that used in working Gay Lussac's
apparatus for saving nitrate of soda, and consists of a series of cooling cisterns
made of Caithness flags, secured with suitable cement. From thence a gutta
percha pipe leads the solutions to an egg-shaped vessel made of metal or wood,
(the former is preferred), and carefully lined with india-rubber or gutta percha,
or it may be made of thick sheets of gutta percha only, but the former plan
is preferred for cheapness. This latter vessel is attached to an ordinary air
pump, by which the liquid contents are forced through a gutta percha pipe,
or a metal pipe lined with india-rubber, to a cistern placed on the top of
No. 1 condenser, from whence a regular supply of the acid solutions can be
obtained as required by means well known to manufacturers.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert Calvert Clapham in the Great Seal Patent Office
on the 11th March 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
CALVERT CLAPHAM, of Walker, in the County of Northumberland, Analytical
Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of September, 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
Robert Calvert Clapham, Her special licence that I, the said Robert Calvert
Clapham, my executors, administrators, and assigns, or such others as I, the
said Robert Calvert Clapham, 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

page_text: and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF BLEACHING POWDER, AND APPARATUS
EMPLOYED THEREIN," upon the condition (amongst others) that I, the said
Robert Calvert Clapham, my executors or administrators, by an instrument
in writing under my or their, or one of their hands and seals, should particu-
larly 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 Robert Calvert Clapham, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the Drawing hereunto
annexed, that is to say:-
My Invention consists of a method of obtaining from a given weight of
common salt a larger quantity of muriatic acid of a strength suitable for
making bleaching powder than is obtained by the methods now commonly
used. In condensing muriatic acid from the decomposition of common salt,
a large part of the muriatic acid has hitherto been found to be of too low a
strength to be applicable to the decomposition of manganese in making
bleaching powder, and the object of the present Invention is to render the
above-named weak acid, which usually varies in strength from 1° to 6° Twaddle,
commercially useful for the above object. I first cool the weak acid solutions
as they usually run from the last or weak condensers used in condensing
muriatic acid in any suitable apparatus, and then pass it down what is called
No. 1 condenser, or the strong acid condenser commonly used when decomposing
common salt in the place of water, or it may be mixed with water, or I expose the
said weak solutions to a stream of weak or waste muriatic acid gas till it arrives
at the required strength, and in either case I then find it of sufficient strength
to use in the manufacture of bleaching powder. The apparatus employed
resembles in principle that used in working Gay Lussac's apparatus for saving
nitrate of soda, and consists of a series of cooling cisterns made of Caithness
flags secured with suitable cement. From thence a gutta percha pipe leads the
solutions to an egg-shaped vessel made of metal or wood, (the former is pre-
ferred,) and carefully lined with india-rubber or gutta percha, or it may be
made of thick sheets of gutta percha only, but the former plan is preferred
for cheapness. This latter vessel is attached to an ordinary air pump, by
which the liquid contents are forced through a gutta percha pipe or a metal
pipe lined with india-rubber to a cistern placed on the top of No. 1 condenser,

page_text: from whence a regular supply of the acid solutions can be obtained as required
by means well known to manufacturers.
The accompanying Drawing is a sectional elevation of so much of the appa-
ratus I employ in connection with my Invention as will be sufficient to illus-
trate the manner in which I carry it into effect.
a is a metal vessel lined with gutta percha, receiving weak acid from a
cistern 6 by the pipe c; d is a pipe leading from the air pump of an engine
to the vessel a; and e is a pipe leading the weak acid forced from the vessel a
to the cistern fat the top of a condenser marked No. 1. No. 1, No. 2, No. 3,
are ordinary condensers, No. 2 and No. 3 of which are surmounted by
water cisterns g and h; i is a pipe leading to the decomposing pans from
No. 1 condenser; k is a pipe leading from No. 2 condenser to the drying
furnace; and is a pipe leading the waste gas from No. 2 to No. 3 con-
denser; m is a pipe leading weak acid to the cistern b.
And having now described the nature of my said Invention and in what
manner the same is to be performed, I declare that I claim,-
First, the improvements in the manufacture of bleaching powder herein-
before described.
Second, the apparatus employed for the manufacture of bleaching powder,
constructed and acting substantially in manner herein-before described and
illustrated in the accompanying Drawing.
In witness whereof, I, the said Robert Calvert Clapham, have hereunto
set my hand and seal, this Ninth day of March, One thousand eight
hundred and sixty-one.
D CALVERT CLADILAM