IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL STONE
Year: 1864

page_text: PROVISIONAL SPECIFICATION left by
at the Office of the Commissioners of Patents, with his Petition, on the
27th February 1864.
I, FREDERICK RANSOME, of Ipswich, in the County of Suffolk, do hereby
declare the nature of the Invention for "IMPROVEMENTS IN THE MANUFACTURE
OF ARTIFICIAL STONE," to be as follows:-
This Invention has for its object improvements in the manufacture of
artificial stone. Artificial stone is now manufactured by me by compounding
sand and similar substances with soluble silicate (silicate of soda or potash)
and then converting the soluble into an insoluble silicate by means of a solution
of chloride of calcium or other soluble salt capable of similarly acting on the
soluble silicate. The chloride of calcium or other salt thus employed remains
in excess in the artificial stone, and if it be afterwards dissolved out, either
intentionally or by exposure to the weather, the stone is left slightly porous.
Now according to my present Invention I treat the artificial stone thus
manufactured with a solution of such a nature as to decompose and precipitate
an insoluble substance from the chloride of calcium or other soluble salt used

page_text: to act upon the soluble silicate. The solution which I find most suitable,
the excess of chloride of calcium and precipitates from it carbonate of lime,
and most commonly employ, is one of carbonate of soda, which decomposes
which is deposited in and well fills the pores of the stone.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Frederick Ransome, in the Great Seal Patent Office on
the 23rd August 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
RANSOME, of Ipswich, in the County of Suffolk, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of February, in the year of our
Lord One thousand eight hundred and sixty-four, in the twenty-seventh year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Frederick Ransome, Her special licence that I, the said Frederick
Ransome, my executors, administrators, and assigns, or such others as I,
the said Frederick Ransome, my 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 "IMPROVEMENTS
IN THE MANUFACTURE OF ARTIFICIAL STONE," upon the condition (amongst
others) that I, the said Frederick Ransome, my executors or administra-
tors, 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 Frederick Ransome, 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 thereof, that is to say:-
artificial stone. Artificial stone is now manufactured by me by compounding
This Invention has for its object improvements in the manufacture of
sand and similar substances with soluble silicate (silicate of soda or potash)
and then converting the soluble into an insoluble silicate by means of a
3

page_text: on
solution of chloride of calcium or other soluble salt capable of similarly acting
on the soluble silicate. The chloride of calcium or other salt thus employed
remains in excess in the artificial stone, and if it be afterwards dissolved out,
either intentionally or by exposure to the weather, the stone is left slightly
5 porous.
Now according to my present Invention I treat the artificial stone thus
manufactured with a solution of such a nature as to decompose and precipitate
an insoluble substance from the chloride of calcium or other soluble salt used
to act upon the soluble silicate. The solution which I find most suitable,
0 and most commonly employ, is one of carbonate of soda, which decomposes
the excess of chloride of calcium and precipitates from it carbonate of lime,
which is deposited in and well fills the pores of the stone.
In carrying out these improvements in the manufacture of artificial stone
I prefer to prepare the artificial stone in the manner heretofore commonly
practised by me and fully described in the Specification of my Patent of the
9th of April, 1861, No. 877, saturating the material with a solution of chloride
of calcium, or it may be of other soluble salt of an alkaline earth, or of the
chloride of aluminum or of iron. The chloride of calcium is, however, the
salt I generally use. The stone being thus made as heretofore, I treat the
same with another solution of such a nature as to decompose the excess of
chloride of calcium or other soluble salt, and precipitate an insoluble substance
in the pores of the stone for the purpose of rendering the same more dense
and compact. In cases where chloride of calcium has been used to act upon
the soluble silicate, I immerse the stone so made in a solution of a carbonate
of soda, (I generally use the bicarbonate, and the solution I prefer should be
as nearly saturated as possible,) and I allow the stone to remain a sufficient
length of time in such solution to decompose all the previously free chloride
of calcium and produce carbonate of lime, which is precipitated throughout
the structure of the stone. The time during which it is necessary to keep
the stone in the solution will vary with the thickness of the block, but twenty-
four hours will in any case be sufficient, although no injury will be done
to the stone by leaving it in the solution a longer time. After being thus
treated the stone is removed from the solution and allowed to remain until
the excess of moisture has drained away, when it is afterwards washed in
water to remove any soluble salt that may be left in the stone. In place of
the solution of carbonate or bicarbonate of soda other solutions may be
employed, although not, I believe, so beneficially; as, for example, a solution
of common alum, in which case sulphate of lime will be formed in the pores
of the stone instead of carbonate of lime; or other suitable decomposing