IMPROVEMENTS IN COPPERS OR BOILERS FOR BOLLING OR CLEANSING ARTICLES OF CLOTHING AND OTHER SUBSTANCES
Year: 1868

page_text: LETTERS PATENT to John Crawford Walker, of Gainsborough Square,.
Hackney Wick, in the County of Middlesex, Gentleman, for the
Invention of "IMPROVEMENTS IN COPPERS OR BOILERS FOR BOLLING OR
CLEANSING ARTICLES OF CLOTHING AND OTHER SUBSTANCES,"
Sealed the 5th March 1869, and dated the 7th September 1868.
PROVISIONAL SPECIFICATION left by the said John Crawford Walker
at the Office of the Commissioners of Patents, with his Petition,
on the 7th September 1868.
I, JOHN CRAWFORD WALKER, of Gainsborough Square, Hackney
Wick, in the County of Middlesex, Gentleman, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN COPPERS OR BOILERS
FOR BOILING OR CLEANSING ARTICLES OF CLOTHING AND OTHER SUBSTANCES," to bo
as follows:-
The object of my Invention is to reduce the labour and time ordinarily
required in the process of boiling or cleansing articles of clothing and
other substances.
My Invention consists of improvements in coppers or boilers, which
may be either portable or fixed (which improved coppers or boilers

page_text: My improvements in coppers or boilers consist,—
First, of an outer boiler or shell, which may be of any form or size,
made of any netal or metals ordinarily employed in the construction of
similar vessels.
And, secondly, one principal feature of my Invention consists of a
vessel or basin (which for convenience I call the "circulator") placed
within the said outer boiler or shell and used in combination therewith,
thus forming together a double copper or boiler, as before indicated.
Sometimes I employ more than one such inner vessell or circulator,
having divisions or chambers provided in or between them. The said
inner vessel or "circulator" may be made of metal or of earthenware,
its size an form being such as to allow of its admission within the
before-mentioned outer boiler or shell, at the same time leaving a space
or chamber all around and beneath its outer surface and between it and
the inner surface of the said outer boiler or shell. The upper edge of
my said inner vessell or "circulator" may be turned over in the form of
a lip made to fit into the outer boiler or shell, or a band of metal may
be substituted for the said lip, and legs of a few inches in length may,
where necessary, be attached to the bottom of the said inner vessel or
circulator to keep it in its place. The sides of the said inner vessel or
circulator are made so to convey to an apex as to leave the before-
mentioned space or chamber around it larger near the bottom than at
the top. In the bottom of the said inner vessel or "circulator "I pro-
vide sundry small apertures, and immediately under the before-described
lip or band, at the top of the "circulator," certain apertures or openings
are made over which narrow ledges are arranged. The extent or size of
the said space or chamber surrounding the inner vessel or "circulator"
must in each case be regulated by the size of the outer copper or boiler,
and the size and number of the said apertures in the apex of the
"circulator" and the opening below the lip or band must be regulated
in like manner. In the case of an ordinary 14 gallon copper or boiler,

page_text: as generally used for domestic purposes, the said space or chamber
surrounding my inner vessel or "circulator" may be about one-fourth
of an inch in width near the top, and from two to six inches, or even
more, in width near the bottom. Thus when my said inner vessel or
"circulator" is placed within the outer boiler or shell a space or
chamber narrow at the top but larger towards the bottom is formed
around it, between which space or chamber and the inner part of my
circulator there is communication through the apertures in the apex and
A natural effect of heat
the openings near the top before described.
applied to water when heated from below in a vessel which also becomes
hot at the sides as well as at the bottom is, as is well known, to create
currents of heated water rising at the circumference and flowing down
towards the centre. In this Invention it has been a special aim to
consult and turn to advantageous account this natural law.
I proceed to perform the operation of washing or cleansing by placing
the articles, fabrics, or substances to be operated upon in the interior
of my said "circulator" (previously soaking and soaping the textile
fabrics), and nearly half filling the before-described boiler with cold
water, adding further soap or other cleansing agents in the usual quan-
tities when required, and lighting the fire beneath in the ordinary
manner. As soon as the water boils it rises naturally between the two
walls enclosing the space or chamber before described, the outer one of
which is very hot, being in immediate contact with the fire, and the
means of egress for the heated water and steam being restricted they are
forced through the said openings in the upper part of the circulator,
upon and
and violently precipitated into the interior of the "circulator"
through the articles of clothing or other substances therein, forcing
their way downwards and through the before-mentioned apertures in the
bottom or apex of the "circulator," when the water is reheated and again
driven up between the walls of the said space or chamber as before.
Thus a very powerful current of boiling water and steam is maintained
in circulation, directly operating upon the articles of clothing or other
substances within the "circulation," and keeping them in continued
agitation until thoroughly boiled or cleansed.
My inner vessel or "circulator," as may be understood from the
foregoing description, can readily be adapted to boilers or coppers already
in use.
I do not confine myself to all or any of the precise details
herein-before given.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Crawford Walker in the Great Soal Patent
Office on the 6th March 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
CRAWFORD WALKER, of Gainsborough Square, Hackney Wick, in the
County of Middlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of September, in the
year of our Lord One thousand eight hundred and sixty-eight, in the
thirty-second year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said John Crawford Walker, Her
special licence that I, the said John Crawford Walker, my executors
administrators, and assigns, or such others as I, the said John Crawford
Walker, ny 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 "I■.
PROVEMENTS IN COPPERS OR BOILERS FOR BOILING OR CLEANSING ARTICLES OF
CLOTHING AND OTHER SUBSTANCES," upon the condition (amongst others)
that I, the said John Crawford Walker, my executors or administrators,
by an instrument in writing under my, or 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 aud immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said John Crawford Walker, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by
the following statement, that is to say :-
The object of my Invention is to reduce the labour and timo ordinarily
required in the process of boiling or cleansing articles of clothing and
other substances.
My Invention consists of improvements in coppers or boilers, which
may be either portable or fixed, which improved coppers or boilers

page_text: I call double or multiple chambered coppers or boilers, having two or
more chambers combined for boiling or cleansing articles of clothing
and other substances, by means of which the water in the copper or
boiler may be heated above the ordinary boiling temperature of 212º,
and the natural action of the currents of the heated water and steam
is controlled and concentrated and rendered more effectual for the
purposes before mentioned.
My improvements in coppers or boilers consist,-
First, of an outer boiler or shell, which may be of any form or size,
made of any metal or metals ordinarily employed in the construction of
similar vessels.
And, secondly, one principal feature of my Invention consists of a
vessel or basin (which for convenience I call a "circulator") placed within
the said outer boiler or shell and used in combination therewith, thus
forming together a double copper or boiler, as before indicated.
Sometimes I employ more than one such inner vessel or "circulator,"
having divisions or chambers provided in or between them. The said
inner vessel or "circulator" may be made of metal or of earthenware,
its size and form being such as to allow of its admission within the
before-mentioned boiler or shell, at the same time leaving a space or
chamber all around and beneath its outer surface and between it and the
inner surface of the said outer boiler or shell. The upper edge, of my
said inner vessel or "circulator" may be turned over in the form of a
lip made to fit into the outer boiler or shell, or a band of metal may be
substituted for the said lip, and legs of a few inches in length may,
where necessary,
be attached to the bottom of the said inner vessel or
"circulator" to keep it in its place. The sides of the said inner vessel
or "circulator" are made so as to converge to an apex as to leave the
before mentioned space or chamber around it larger near the bottom
than at the top. In the bottom of the said inner vessel or "circulator
I provide sundry small apertures, and immediately under the before-
described lip or band at the top of the "circulator" certain apertures
of openings are made, over which narrow ledges are arranged. The
extent or size of the said space or chamber surrounding the inner vessel
or "circulator" must in each case be regulated by the size of the outer
copper or boiler, and the size and number of the said apertures in the
apex of the "circulator" and the openings below its lip or band must
be regulated in like manner. In the case of an ordinary fourteen gallon
"

page_text: copper or boiler, as generally used for domestic purposes, the said space
or chamber surrounding my inner vessel or "circulator" may be about
one-fourth of an inch in width near the top, and from two to six inches,
or even more, in width near the bottom. l'hus when my said inner
vessel or "circulator" is placed within the outer boiler or shell a space
or chamber narrow at the top but larger towards the bottom is formed
around it, between which space or chamber and the inner part of my
"circulator" there is communication through the apertures in the
apex and the openings near the top before described. A natural effect
of heat applied to water when heated from below in a vessel which also
becomes hot at the sides as well as at the bottom is, as is well known,
to create currents of heated water rising at the circumference and flowing
down towards the centre. In this Invention it has been a special aim
to consult and turn to advantageous account this natural law.
I proceed to perform the operation of washing or cleansing by placing
the articles, fabrics, or substances to be operated upon in the interior
of my said "circulator" (previously soaking and soaping the textile
fabrics) and nearly half filling the before described boiler with cold.
water, adding further soap or other cleansing agents in the usual
quantities when required, and lighting the fire beneath in the ordinary
manner. As soon as the water boils it rises naturally between the two
walls enclosing the space or chamber before described, the outer one
of which is very hot being in immediate contact with the fire (and the
means of egress for the heated water and steam being restricted) they
are forced through the said openings in the upper part of the "circulator"
and violently precipitated into the interior of the "circulator" upon and
through the articles of clothing or other substances therein, forcing their
way downwards and through the before-mentioned apertures in the
bottom or apex of the "circulator," when the water is reheated and
again driven up between the walls of the said space or chamber as
before. Thus a very powerful current of boiling water and steam
is maintained in circulation, directly operating upon the articles of
clothing or other substances within the "circulator," and keeping them
in continual agitation until thoroughly boiled or cleansed.
My inner vessel or "circulator" (as may be understood from the fore-
going description) can readily be adapted to boilers or coppers already
in use.
I do not confine myself to all or any of the precise details herein-
before given.

page_text: And in order to explain my said Invention more completely I now
roceed to describe the best means I am acquainted with for carrying
he same into practical effect, reference being had to the illustrative
Drawing accompanying these Presents, and to the numeral figures and
etters of reference marked thereon respectively. as follows:-
Figure 1 represents a top plan view of a boiler or copper constructed
according to my said Invention; Figure 2 is a transverse and vertical sec-
tion taken through the line A, B, at Figure 1. Similar letters of reference
are employed to denote corresponding parts at each of these Figures.
The arrows denote the circulation of the water when the boiler or
copper is in action. A is a "lining" or "inner vessel," so adapted to
an ordinary laundry copper or boiler B, or to coppers or boilers employed
for other purposes, as to form in combination with such copper or boiler
a "double copper" or "double boiler," the functions and advantages
of which are herein after described. This inuer vessel, which I call the
"circulator," may be made of the same material as the boiler in con-
nection with which it is intended to be used, or of any other suitable"
material. I generally employ sheet copper or sheet iron, which latter
should be "galvanized" after the circulator is made. The circulator
is suspended in the boiler by three strips of metal a, a, a, which are
riveted to the inner part of the circulator at the top equidistant from
each other, and bent over the top of the circulator in such a way as to
"clip" upon the top of the boiler B. The top margin of the circulator
is so turned over as to produce a flange around the top one-eighth of
an inch in width. The diameter of the circulator A near the bottom
thereof is less than that of the boiler B in which it is placed, and the
circulator is not quite so deep as the said boiler, as represented; its form
and size are such that when suspended in the boiler a narrow space is
left all round the top, and this space becomes gradually larger until it
reaches the bottom. The bottom of the circulator may be conical, or it
may be nearly oval, like the bottom of the boiler. The space between
the circulator and the boiler may be about quarter of an inch wide
at the top, and from an inch and a quarter to an inch and a half wide
at the bottom of the "sides," and from two to three inches deep between
the bottom of the circulator and the bottom of the boiler. Around the
top of the circulator and immediately under and close to the flange

page_text: thereof an india-rubber band C about three-quarters of an inch wide and
a quarter of an inch thick, prepared to stand a tolerably high heat, is
placed. Although a fixed band of metal or a band of felt may be employed,
a flexible rubber band is preferable. The object of this band is to closely
fill up and "bridge" over the space left between the top of the circulator
and the top of the boiler, and the object of the flange above it is to
prevent the band from slipping upwards when the circulator is pressed
down into the boiler. Immediately under the band C just described,
and close to it and running parallel with it, and equidistant from each
other, sundry openings c, c, are formed in the circulator, the aggregate
length of which is equal to about five-twelvths of the circumference of
the top of the circulator, aud the width or depth about a quarter of an
inch. I propose to employ four of these openings in a circulator
designed for a boiler holding ten gallons or less of water, although the
number of such said openings may be increased or diminished according
to fancy I propose however to have five of these openings in a cir-
culator designed for a boiler holding fifteen gallons; six for a circulator
designed for a twenty gallon boiler; seven for a thirty gallon boiler, and
so on in about the same proportions. The bottom of the circulator is
perforated with sundry holes d, d, of about half an inch in diameter.
The bottom of the circulator of a boiler designed to be used in cleansing
or dying textile fabrics 1 propose to perforate with very nearly, if not quite,
three of theso holes for every gallon of liquid the boiler is computed to
hold. Thus the bottom of a circulator for a ten gallon boiler is perforated
with thirty half-inch holos; the bottom of a circulator for a twenty
gallon boiler is perforated with sixty half-inch holes, and so on in the
same proportion. When the boiler is used for obtaining extracts from
organic matter the number of half-inch holes in the bottom of the
circulator should be not less than two for each gallon the boiler is com
puted to hold; and when the boiler is employed in concentrating
solution one half-inch hole in the bottom of the circulator for cach
gallon the boiler holds 1 consider sufficient. Two "drop" handlea D
are attached opposite each other to the inside of the top of the circulator,
by which the circulator is put into and taken out of the boiler. It is
sometimes found advisable, particularly with large boilers, or in the
process of "dying" textiles for the purpose of separating the articles
to be acted upon, to place one or more false bottoms of open wirework
in the circulator, or what is even better than the false bottoms where
large boilers are employed is a cone of open wirework about half the

page_text: size and height of the circulator place upon its base within the cir-
culator, upon which the articles to be treated are spread. Neither the
false bottoms of wirework however, nor the wirework cone are essential
to the satisfactory working of the apparatus. Under all ordinary circum-
stances a raised lid may or may not be employed.
false bottoms of wirework however, nor the wirework cone are essential
to the satisfactory working of the apparatus. Under all ordinary circum-
stances a raised lid may or may not be employed.
OPERATIONS OF THE ABOVE IMPROVEMENTS.
When this "double boiler" is about half filled with cold water
(containing a small quantity of finely sliced soap and the usual
quantity of washing soda or washing powders) and the clothes (having
been previously soaked and soaped) are thrown into the boiler and an
efficient heat is applied, a part of the steam generated rises through
the holes in the bottom of the circulator and penerates through the
fabrics contained therein, acting upon and loosening to some extent the
"dirt" that attaches to such fabrics, while at the same time a volume
of water and steam (highly heated by contact with the outer wall of
the boiler, and through the resistance offered by the contraction of the
chamber towards the top and the restriction of the means of egress at
the top rises in the outer chamber and is forced through the openings
in the top of the circulator and precipitated upon the articles contained
within the inner chamber of the boiler, through which and the holes in
the bottom of the circulator the water and condensed steam rapidly
pass, having been preceeded regularly by a quantity of water sufficient
Thus a volume of steam
to supply the displacement from below.
continuously rises and penetrates through the fabrics from below, whilst
numerous streams of highly heated water and steam are precipitated
from above and maintained in circulation through the fabrics in an
opposite direction, these different actions and influences combining to
loosen and remove all foreign matters that may temporarily attach to
the articles in the boiler. This result is generally accomplished in from
fifteen to twenty-five minutes' time, and it is estimated that nearly all
the hard labour and fully half the time usually employed in washing and
cleansing wearing apparel and household linen is saved by this process.
It may be added that any small quantities of loose dirt which may still
adhere to the articles after they are removed from the boiler are quickly
and easily removed in the after and usual process of "sudding" and
rinsing. In washing "after batches" the larger part of the water pre-
viously used (and if the water previously used contains much dirt the

page_text: whole of it) should be removed and a proper supply of clean cold water be
substituted. The articles should be placed in the boiler before the water
becomes hot. After each day's washing the circulator is removed from the
boiler and both are cleansed while the metal is still warm; when not in use
the circulator should be kept dry. The process of "dying" textile fabrics
with this apparatus is similar to that of cleansing articles of clothing,
except that the colouring matters are substituted for the washing ingre-
dients, the differences in time and manipulation employed being subject
to the nature of the work and necessarily. determined by the judgment
of the operator. No explicit directions for the use of this apparatus in
obtaining extracts from organic substances or in concentrating solutions
would be applicable to the different cases in which the double boiler is
found of value, and the fact that persons employed in work of this sort
are generally well instructed, each in his own speciality, would render
all arbitrary rules superfluous.
Having now fully described and set forth the nature and object of my
said Invention for "Improvements in Coppers or Boilers for Boiling or
Cleansing Articles of Clothing and other Substances," together with the
best means I am acquainted with for carrying the same into practical
effect, I would remark in conclusion that I do not intend to confine
myself to the precise details of construction and proportions above
described and represented; but what I claim as my Invention and
intend to be secured to me by the herein-before in part recited Letters
Patent is as follows:-
I claim the connecting of an inner vessel or lining of the general
character herein-before described with an outer vessel, in the manner and
for the purposes herein-before stated, as constituting improvements in
coppers or boilers.
In witness whereof, I, the said John Crawford Walker, have here-
unto set my hand and seal, this Sixth day of March, in the
year of our Lord One thousand eight hundred and sixty-nine.
J. C. WALKER. (L.S.)