AN IMPROVED METHOD OF PREPARING OR TREATING CEMENTS FOR THE PURPOSE OF RENDERING THEN APPLICABLE FOR THE PRODUCTION OF ARTIFICIAL STONE, AND ARCHITECTURAL ORNAMENTS
Year: 1870

page_text: LETTERS PATENT to Charles James Busk, of Pancras Lane, in the
City of London, Merchant, for the Invention of "AN IMPROVED
METHOD OF PREPARING OR TREATING CEMENTS FOR THE PURPOSE OF RENDERING
THEN APPLICABLE FOR THE PRODUCTION OF ARTIFICIAL STONE, AND
ARCHITECTURAL ORNAMENTS." - A communication from abroad by
Robert Parish Busk, of Lille, in the Empire of France.
-
Scaled the 4th October 1870, and dated the 5th April 1870.
PROVISIONAL SPECIFICATION left by the said Charles James Busk
at the Office of the Commissioners of Patents, with his Petition,
on the 5th April 1870.
[6
I, CHARLES JAMES BUSK, of Pancras Lane, in the City of London,
Merchant, do hereby declare the nature of the said Invention for
AN IMPROVED METHOD OF PREPARING OR TREATING CEMENTS FOR THE PURPOSE
OF RENDERING THEM APPLICABLE FOR THE PRODUCTION OF ARTIFICIAL STONE, AND
ARCHITECTURAL ORNAMENTS," to be as follows:-
This Invention relates, firstly to the employment of limestone, shale,
or shale found in limestone quarries for the manufacture of hydraulic

page_text: cement. The shale as it is dug out of the quarries or mines where it is
found is calcined, and then finally ground and sifted so as to remove
from the fine powder all grit and coarse particles.
In using the cement for the manufacture of artificial stone or
architectural ornaments it may be used either neat or with the addition t
of such a proportion of sand, pounded stone, or marble, or other analogous
substances as may be found desirable to add, according to the quality of
stone or the nature of the article or kind of "grain" it is desired to
produce. To the cement and other materials when mixed is added as much
solution of silicate of soda or potash as will be necessary to bring the 1
ingredients into such a pasty or semi-pasty state as will cause the particles
to adhere together when submitted to pressure. In practice it is found
desirable not to make the ingredients too wet by the addition of too large
a proportion of the silicate solution.
The Invention also consists in using the silicates of soda and potash 1
in combination with Portland cement, Roman cement, and other hard or
hydraulic cements, either alone or in combination with other substances.
The addition of the silicate makes articles made of these cements much
harder and more durable than when the cements are heated or used in
the ordinary manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charles James Busk in the Great Seal Patent
Office on the 5th October 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
JAMES BUSK, of Pancras Lane, in the City of London, Merchant, send :
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of April, in the year
of our Lord One thousand eight hundred and seventy, in the thirty-
third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Charles James Busk, Her special
licence that I, the said Charles James Busk, my executors, administrators,
and assigns, or such others as I, the said Charles James Busk, my
executors, administrators, and assigns, should at any time agree with,

page_text: 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
"AN IMPROVED METHOD OF PREPARING OR TREATING CEMENTS FOR THE PURPOSE OP
RENDERING THEM APPLICABLE FOR THE PRODUCTION OF ARTIFICIAL STONE, AND
ARCHITECTURAL ORNAMENTS," being a communication to me from abroad
by Robert Parish Busk, of Lille, in the Empire of France, upon the
condition (amongst others) that I, the said Charles James Busk, 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 and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Charles James Busk, 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)
This Invention relates to the employment of limestone shale or shale,
found in limestone quarries for the manufacture of hydraulic cement,
such for instance as that made at Tournai, in combination with soluble
silicates as herein-after set forth for the purpose of producing artificial
stone and architectural ornaments of a harder and more durable
description than heretofore. The shale as it is dug out of the quarries
or mines where it is found (as for instance at Tournai) is calcined, and
then finely ground and sifted so as to remove from the fine powder all
grit and coarse particles. This Tournai and other hydraulic cements,
such as Portland cement, Roman cement, or Vassy and others, that are
used for making artificial stone and for ornamental and architectural and
other purposes may be employed whether such cements be used alone or
in combination with sand, chalk, clay, pounded stone, marble or other
analogous substances. The material I employ for the above mentioned
purpose is a solution of silicate of soda, or of silicate of potash, or other
soluble silicate which is to be mixed in variable proportions (with the
water as ordinarily employed in treating cements) with the cements and
other ingredients used for producing artificial stone so as to bring these
materials into such a pasty or plastic or semi-pasty state, as to cause the

page_text: particles to adhere together when submitted to pressure or when poured
into moulds.
In adapting my Invention to the manufacture of artificial stone, or
architectural ornaments, or other purposes, one of two distinct processes
are necessary, viz. moulding or casting according to the kind of article or
ornament intended to be made. The process by "moulding" produces
the harder and more solid and durable stone, and should be followed when
rigid moulds of a hard and strong material, such as wood, metal, plaster,
&c. can be employed and into which the plastic mass may be pressed or
rammed without injuring them. The following proportions of ingredients
may be used according to the quality of stone desired.

page_text: "
proportions the materials after being thoroughly mixed and combined
in a mortar mill or by other suitable means become a slightly moist and
plastic mass which must be quickly rammed or pressed into the moulds.
The process by casting" must be adopted when it is desired to make
delicate figures or under cut works which can only be made in
flexible or clastic moulds, or in such as will not bear having the
materials rammed into them. The above mentioned materials may be
employed, and in similar proportions with exception of the silicate, the
quantity of which should be slightly increased as the dilution with
water necessary to render the plastic mass sufficiently fluid for "casting"
or pouring into the moulds (instead of ramming) reduces its strength or
hardening properties to a trifling extent, therefore instead of 1.25 parts.
of silicate (as recommended for“ moulding,”) take 1·50 parts, and instead
of 150 parts (in the No. 3) take 1.75 or 1·80, and add thereto as much
water as will bring the specific gravity from fifty degrees (Beaumé) to
twenty degrees or twenty-five degrees. I combine well the cement with
the diluted solution of silicate and then add the sand and chalk, or
other ingredients employed, which should be previously mixed together,
and I then incorporate the whole. After being stirred gently for a
few moments to get rid of air bubbles, the mixture may be run into the
moulds like plaster of Paris.
I do not confine myself to any of the above given proportions of
materials, which are only given because in practice they have furnished
good samples of stones, the proportions are susceptible of many variations
and will produce good results. It requires two or three or perhaps
four hours if the figure is very delicate before the "cast" articles can be
safely taken from the flexible or clastic mould, whereas “moulded"
stones or ornaments are ready to be withdrawn immediately after they
are moulded.
Artificial stones or articles made by either of the above processes
should be left to dry gradually by themselves. They require no further
operation to become hard and are unattackable by water in a few days and
will continue to harden with time. The effects of time, however, can be
hastened by first damping the moulded article a few days after it has
been made, and then after a further few days interval putting it into
water for a week or two. The articles may be further hardened and
improved in quality if (a few days after they have been withdrawn from
the moulds) they are soaked in a strong solution of alum in water for a

page_text: week or ten days according to their dimensions. At the end of that
time, and after being allowed to dry gradually their solidity and strength
will be found to have greatly increased.
Having now described my Invention of an improved method of
preparing or treating cements for the purpose of rendering them
applicable for the production of artificial stone and architectural
'ornaments, and having explained the manner of carrying the same into
'effect, I claim as the Invention secured to me by Letters Patent, the
combining in the manner above described with Tournai, Portland,
Roman, Vassy, and other hydraulic cements, solutions of silicate of soda,
or of silicates of potash or other soluble silicate as herein set forth, for
the purpose of producing and hardening and rendering more durable
artificial stones for building or for architectural ornaments and other
purposes.
In witness whercof, I, the said Charles James Busk, have
hereunto set my hand and seal, the Thirtieth day of September,
in the year of our Lord One thousand eight hundred and