IMPROVEMENTS IN THE MANU- FACTURE OF ARTIFICIAL STONE
Year: 1882

page_text: LETTERS PATENT to Richard Searle of 23 Amhurst Road Hackney in the
County of Middlesex for an invention of IMPROVEMENTS IN THE MANU-
FACTURE OF ARTIFICIAL STONE.
PROVISIONAL SPECIFICATION left by the said Richard Searle at the Office
of the Commissioners of Patents on the 28th June 1882.
RICHARD SEARLE of 23 Amhurst Road Hackney in the County of Middlesex
IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL STONE.
My invention consists in an improved method of making artificial stone, the
cementitious portion of which is Portland Cement, and which is mixed with a
suitable aggregate of hard material, such as granite, or other stone, sand, slag,
metal, or similar material, of a size suitable for such aggregation or admixture, and
which artificial stone when completely manufactured is intended, and suitable for
all purposes in which natural stone may be employed; as for instance, paving, and
the erection of buildings and other works; my improved mode of manufacture is
as follows: having mixed together (in a dry state) the Portland Cement, and
selected aggregate in any chosen proportions, as ordinarily done, I now apply my
improved method of manufacture, by adding to the mass artificially heated water
of any temperature, the heat to be determined according to the judgment of the
operator, and varied as may be desirable, according to the different sized blocks, or
character of the stone required, and which may also be found necessary by
alteration of the temperature of different seasons; the materials thus treated is
then placed in mould of any forms desired and whilst the material is still in a
plastic, or semi-fluid state I remove the air which is mixed with it by any known
mode of exhaustion; but I preferably adopt the following plan: I enclose the
material in the mould in a box, or covering (impervious to the atmosphere,) to
which is attached a pipe communicating with an exhausted vessel, which pipe is
fitted with a cock, so that when the material is so enclosed, the cock is opened
causing the air to rush into the exhausted vessel, and to an extent relieving the
material from pressure, and consequently enabling the air thus imprisoned to pass

page_text: into the partial vacuum chamber; by which means the stone is improved by an
increased solidity, and consequent strength or among other methods I can apply
exhaust pumps direct: this second part of my improved method of making
artificial stone is distinct from the improvement claimed by the use of artificially
heated water, and may be omitted in the manufacture if so desired; the two claims
being independent of each other, and so may each be used alone, and separately.
Not only is a denser and more solid stone obtained by the extraction of the air as
herein described, but a considerable saving of time is effected in the manufacture
by the use of heated water, as well also in the number of moulds required; by
causing an earlier and more rapid crystallization, and consequent induration, so
that the stone can be sooner removed from the moulds, and is fit for use at a much
earlier period than artificial stone not made with artificially heated water: the
stones when sufficiently hard are taken out of the moulds and placed in a bath
formed of a solution of silicate of so la inade from the natural soluble silicate
cominonly called Farnham Stone.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Richard Searle in the Great Seal Patent Office on the 27th November
1882.
RICHARD SEARLE of 23 Amhurst Road Hackney in the County of Middlesex,
"IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL STONE
"
My said Invention consists in an improved method of making artificial stone,
the cementitious portion of which consists of Portland rement mixed with a
suitable aggregate of hard material, or core, such as granite or other stone, sand,
slag, metal, or some such material of a size suitable for such aggregation, or
admixture, and which artificial stone when silicated as herein after described I call
"Victoria stone" and is intended and suitable for all purposes in which natural
stone may be employed, being especially valuable for paving and in the erection of
buildings and other works either submarine or otherwise; -my improved mode of
manufacture is as follows; having mixed together in a dry state the portland
cement and selected aggregate in any chosen proportions as ordinarily done, I now
apply my improved method of manufacture by adding to the mass (so mixed)
artificially heated water of any desired temperature the degree being determined
according to the judgment of the operator, and varied as may be desirable con-
sequent upon the different sizes blocks or forms of the stones required or on account
of differences of temperature of the atmosphere arising from the various seasons;
the materials thus treated are then placed in moulds of any desired shape and
whilst in a plastic or semi-fluid state I remove the air which is mixed with it by
any known mode of exhaustion, but I preferably adopt the following plan. I
enclose the material in the mould in a box or by a covering impervious to the
atmosphere) to which is attached a pipe communicating with an exhausted vessel
which pipe is fitted with a cock or valve so that when the material is so enclosed
(as above described) the cock is opened causing the air to rush into the exhausted
vessel and to an extent relieving the material from pressure and consequently
enabling the air thus confined in it to pass into the vacuum chamber by which
means the stone is improved by an increased solidity and consequent strength; but
instead of this particular process of exhaustion I can among other methods apply
air pumps direct; this second part of my improved method of making artificial
stone is to be understood as being altogether separate and distinct from the
improvement claimed before hand of using artificially heated water, as it is equally
applicable for and in the manufacture of artificial stone made with cold water the
two improved methods being independent of each other and consequently each is
complete in itself, and may therefore he used either alone or in combination―The
value of the improved method I claim of using artificially heated water in the
making of artificial stone from Portland Cement consists in obtaining a stone of
increased strength and durability and also in the saving of time in the manufacture
thereof and likewise in the lesser number of moulds required, by causing an earlier
and more rapid crystallization and consequent induration than takes place in
portland cement stone not made with artificially heated water, so that the stones
can be sooner removed from the moulds and are fit for use at an earlier period than
by the ordinary way of making artificial stone the cementitious part of which is
Portland cement mixed with cold water; the stones (made under either the im-
proved methods) when sufficiently hard are taken out of the mould and placed in
a bath composed of a solution of silicate of soda-made from the natural soluble
silicate of soda-commonly called Farnham stone by which means the stone becomes
silicated throughout.

page_text: Having thus stated the particulars of my improved method of making artificial
stone from Portland Cement it must now be understood that my claim altogether
consists in, and is limited to,
Firstly. In the making of artificial stone the cementitious portion of which is
Portland Cement and not lime or any other kind of cement or binding material
mixed with artificially heated water as I am aware that the use of hot water has
been claimed for mixing with cementitious materials such as line for making
artificial stone while my claim as already. stated discarding the use of lime and
other cementitious materials is confined to the manufacture of artificial stone made
from Portland cement, mixed with artificially heated water; and secondly by the
withdrawal of the air from the materials used in making artificial stone mixed
either with cold or artificially heated water by any known mode of exhaustion as
generally claimed by me.
In witness whereof I the said Richard Searle have hereunto set my hand and
seal this twenty seventh day of November in the year of our Lord one
thousand eight hundred and eighty two.