Improvements in or relating to the Manufacture of Artificial Stone.
Year: 1899

page_text: Date of Application, 18th Sept., 1899-Accepted, 16th Dec., 1899
COMPLETE SPECIFICATION.
Improvements in or relating to the Manufacture of Artificial Stone.
I, WILLIAM OWEN, Engineer, of Pontsarn, Woking, in the County of Surrey,
do hereby declare the nature of this invention and in what manner the same is
to be performed, to be particularly described and ascertained in and by the follow-
ing statement:-
This invention relates to the manufacture of artificial stone, its principal
feature being the immersion of compressed blocks of the ingredients of such
stones, (say lime and sand, slaked) in hot water under pressure to complete their
manufacture in a manner which fits them for immediate use. A further feature
of this invention is the manufacture of an artificial stone by a novel method
characterized by several stages, the order, nature and duration of which are
hereinafter detailed.
In the novel manufacture of artificial stone above referred to about eight to.
ten parts by weight of sand and one part by weight of lime both in a dry state
are mingled, then slaked and allowed a period of rest exposed to the atmosphere
in order that the slaking may take complete effect, then further mingled in a
machine of any convenient kind, preferably a revolving pan in which they are
subjected to the action of edge runners, the mixture being after compressed into
blocks which subsequently are allowed a period of rest of about twenty-four
hours so that they may slightly harden by natural evaporation, the blocks being
finally immersed for six to ten hours in hot water having a pressure of at least
85 lbs. (absolute) per square inch, and a temperature of not less than
316° Fahrenheit.
The subjection of blocks of the ingredients of artificial stone of the nature
described to hot pressure-water is an important feature of this invention whether
the proportions of sand and lime employed be those above specified or not.
The further mingling of the mixture above referred to, after the operation
of slaking, that is to say the mixing which occurs just prior to compression of
the mixture into blocks, may be omitted if desired, but it is preferable that it
should be included.
Any usual or convenient apparatus may be employed in the carrying out of
the manufacture of artificial stone by the method above specified. The preli-
minary mixing of the sand with the lime may be effected manually or mechani-
cally. The compression of the blocks is conveniently effected by a hydraulic
or steam or screw press fitted with dies such as will give the desired size, and
shape to the compressed blocks; any convenient construction of these well-
known kinds of press and dies can be adopted. The subjection of the com-
pressed blocks to the influence of hot water under pressure as described, may
take place in a chamber (into which they can be-run-upon-trolleys) which is
provided with a door-making a fluid tight joint with it after the trolleys have
entered.
It is desirable that the hot pressure-water aforesaid be maintained at the
desired temperature throughout the period of six to ten hours for which the
blocks are subjected to it; to enable this to be easily done, heating conduits

page_text: may be provided within the chamber and supplied with steam from a suitable
external source, or the chainber and its contents can be kept hot by hot gases
passed through flues situated in proximity to the chamber, or made to surround
it.
The blocks produced by the process above described are ready for use imme-
diately upon their withdrawal from the hot water.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what
I claim is
1. A method of manufacturing artificial stone wherein blocks of the ingre-
dients of the stone are immersed in hot water which has a pressure of at least
85 lbs. (absolute) per square inch and a temperature of not less than
316° Fahrenheit.
2. A method of manufacturing artificial stone wherein blocks of mingled sand
and lime slaked and compressed are immersed in hot water which has a pressure
of at least 85 lbs. (absolute) per square inch and a temperature of not less than.
316° Fahrenheit.
3. A method of manufacturing artificial stone wherein eight to ten parts by
weight of sand to one part by weight of lime are mingled, then slaked and
allowed a period of rest, then further mingled the resulting mixture being after-
wards compressed into blocks subsequently allowed a period of rest, and finally
immersed from six to ten hours in hot water having a pressure of at least 85 lbs.
(absolute) per square inch and a temperature not less than 316° Fahrenheit.
Dated this 15th day of September 1899.
WILLIAM OWEN.
Boult, Wade & Kilburn,
Agents for the Applicant.