An IMPROVED PROCESS OF HARDENING TILES AND OTHER MOULDED ÅRTICLES.
Year: 1872

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
"
in the County of Middlesex, Patent Agent, for the Invention of "An
IMPROVED PROCESS OF HARDENING TILES AND OTHER MOULDED ÅRTICLES.'
A communication from abroad by Jean Larmanjat, of Paris, Civil
Engineer.
Sealed the 10th October 1872, and dated the 23rd April 1872.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 23rd April 1872.
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of the
said Invention for "AN IMPROVED PROCESS OF HARDENING TILES AND OTHER
MOULDED ARTICLES," to be as follows:
This Invention relates to an improved method of indurating paving
and other tiles or moulded articles composed of materials having a base
of lime or cement by the application of steam. It is well known that
products made of hydraulic lime and cements long remain in a porous
condition whatever the degree of pressure to which they may have been

page_text: subjected, they consequently possess but little coherence, and are not fit
for use in less than one to six months after being made. In addition to
this the tiles so made do not retain their freshness of color; as owing to
the time required to harden them by the combined action of water and
air in the ordinary way, the moisture contained in the tile collects in
the surface and tarnishes the color.
According to the improved process of this Invention the tiles are.
quickly indurated and the colors at same time permanently fixed.
The following is the method of operation:-A few days after the
articles have been moulded and which are then in a porous condition, 1
they are placed in a chamber into which steam is introduced which
condenses on the sides of the chamber and on the surfaces of its contents:
The articles being of a porous nature are readily permeated by the con-
densed steam which becomes immediately absorbed. The period of
absorption varies more or less according to the nature and size of the 1
articles.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal
Patent Office on the 22nd October 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER 2
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
**WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of April, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty- 2
fifth year of Ier reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Alexander Melville Clark, Her special
licence that I, the said Alexander Melville Clark, my executors, admi-
nistrators, and assigns, or such others as I, the said Alexander Melville
Clark, my executors, administrators, and assigns, should at any time 3
agree with, and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make,
usc, exercise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"AN IMPROVED PROCESS OF HARDENING TILES AND OTHER MOULDED ARTICLES," 3
°

page_text: à communication to me from abroad by Jean Larmanjat, of Paris,
Civil Engineer, upon the condition (amongst others) that I, the said
Alexander Melville Clark; my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said In-
vention, 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 Alexander Melville Olark, 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, reference being had to the accom-
panying Sheet of Drawings and to the letters and figures marked thereon
(that is to say):—
"
This Invention relates to a method of rapidly indurating paving and
other tiles or moulded articles composed of materials having a base of
lime or cement by the application of steam. It is well known that
products made of hydraulic lime and cements in the usual manner long
remain in a porous condition whatever the degree of pressure to which
they may have been subjected, they consequently possess but little
coherence and are not fit for use in less than from one to six months
after being made. Besides this the tiles so made do not retain their
freshness of color, as owing to the time required to harden them by the
action of water and air in the ordinary way the moisture contained in
the tile exudes and remains on the surface and tarnishes the colors.
According to the process of this Invention the tiles are quickly
indurated and the colors at same time permanently fixed.
The following is the method of operation:-A few days after they
have been moulded and when they are in a porous condition, the articles
are placed in a chamber into which steam is introduced with or without
slight pressure, which steam condenses on the sides of the chamber and
on the surfaces of its contents. The articles being of a porous nature are
readily permeated by the steam which becomes immediately condensed
and remains absorbed. The period of absorption varies more or less
according to the nature and size of the articles.
In order to better explain the method of operation a specimen appa-
ratus to be used in this improved indurating process is shown in the
accompanying Drawine.

page_text: Figure 1 is a central vertical section of the apparatus; Figure 2 being
a longitudinal section on line 1-2, of the steam generator and chamber;
while Figures 3 and 4 show detached views of the tray or frame on
which the tiles are placed on trucks to be conveyed into the steam
chamber.
A is a steam boiler and B a rectangular chamber of wood, masonry,
or other material connected by a pipe C with the steam generator. Two
lines of rails E are provided in the steam chamber for running the trucks
D carrying the articles in and out of the chamber. The articles aro
placed on trays such as that shown at F, Figures 3 and 4, which trays -
are placed one on the other as shown and serve to keep the articles
separate and ensure free access of steam to all parts.
E
Having described the nature of the Invention, and in what manner the
same is to be performed, I declare that what I claim as the Invention
to be protected by the herein-before in part recited Letters Patent is, 1
the method of rapidly indurating tiles and other moulded products
composed of hydraulic lime or cement by the aid of steam, substantially
as herein described.
In witness whereof, I, tho said Alexander Melville Olark, have
hereunto set my hand and seal, this Twenty-second day of October,
in the year of our Lord One thousand eight hundred and seventy-
two.