IMPROVEMENTS IN THE TREATMENT OF NATURAL AND ARTIFICIAL STONE, AND OF ARTICLES COMPOSED OF POROUS CEMENTS OR PLASTER, FOR THE PURPOSE OF HARDENING AND COLORING
Year: 1853

page_text: LETTERS PATENT to Barnabas Barrett, of. Ipswich, Sculptor, for
the Invention of "IMPROVEMENTS IN THE TREATMENT OF NATURAL
AND ARTIFICIAL STONE, AND OF ARTICLES COMPOSED OF POROUS
CEMENTS OR PLASTER, FOR THE PURPOSE OF HARDENING AND COLORING
Sealed the 29th October 1853, and dated the 30th April. 1853.
PROVISIONAL SPECIFICATION left by the said Barnabas Barrett
at the Office of the Commissioners of Patents, with his Petition,
on the Oth-April 1853.
I, BARNABAS BARRETT, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE TREATMENT OF NATURAL AND ARTI-
FICIAL STONE, AND OF ARTICLES COMPOSED OF POROUS CEMENTS OR PLASTER,
FOR THE PURPOSE OF HARDENING AND COLORING THE SAME," to be as fol-
Clows:-
This Invention relates to certain means of indarating stone, cement,
plaster, and other like porous bodies, and thereby giving them the pro-
perty to resist moisture, and also, in some cases, improving their appear-.
ance, as well as increasing their durability. It has hitherto been the
practice, in indurating stone, &c., to use a very high degree of heat, in

page_text: however, has been found highly detrimental to the material under
operation, and in many cases has failed to produce the desired effect.
To remedy these evils I enclose the stone or other materials to be
acted upon in an air-tight chamber, and exhaust or partially exhaust
the same, and then allow the indurating substance, whether hot or cold,
to trickle down or flow into the chamber to fill the vacuum, the effect
of which will be that the liquid indurating substance will readily find
its way into the pores of the stone or other material, and become in-
corporated therewith. The substances which I prefer to employ in
connection with this mode of impregnating are the following; but it
should be remarked that some of them may also be used in the manner
of a paint.
Indurating Mixtures.
1st. Resin dissolved in naptha, spirits of wine, or turpentine, mixed
with gutta percha dissolved in coal tar naptha, and when warmed
with steam heat, mixed with oil or any other greasy materials. After
which, anti-corrosia ground down and well mixed with the above. This
can be used for exterior purposes for hardening and rendering imper-
vious to moisture.
2nd. Gutta percha dissolved in coal tar or other solvent.
3rd. Seedlac or shell-lac, Venice turps, gum animi, with or without
gutta percha, dissolved in spirits of wine or turpentine (cold solution).
4th. Unslacked lime, with oil or soft soap, Russia tallow, mixed with
it whilst slacking; when well slacked to be placed in a copper with
alum water and "anti-corrosia" ground up, copperus and solution made
from potatoes, beer settlings. When all this has been well boiled and
mixed together, let it settle and draw off the solution. This can be used
cold for the exterior of old or new buildings, and can be used for
injecting into stone and work before it is erected.
5th. Sulphur mixed with gutta percha, after being dissolved by heat.
6th. Sulphur dissolved in acid, and mineral substances, mixed to form
a solution.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Barnabas Barrett in the Great Seal Patent Office,
on the 29th October 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
BARNABAS BARRETT, of Ipswich, Sculptor, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of April, in the year
of our Lord One thousand eight hundred and fifty-three, in the six-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Barnabas Barrett, Her special licencé
that I, the said Barnabas Barrett, my executors, administrators, and
assigns, or such others as I, the said Barnabas Barrett, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all tinies 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 TREATMENT OF NATURAL AND ARTIFICIAL STONE, AND OF ARTICLES
COMPOSED OF POROUS CEMENTS OR PLASTER, FOR THE PURPOSE OF HARDENING
AND COLORING THE SAME," upon the condition (amongst others) that I,
the said Barnabas Barrett, by an instrument in writing under my
hand and seal, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be.per-
formed, 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 Barnabas Barrett, do hereby
declare the nature of my 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 certain means of indurating stone, cement,
plaster, and other like porous bodies, and thereby giving them the pro-
perty to resist moisture, and also, in some cases, improving their appear-
ance, as well as increasing their durability.
It has hitherto been the practice, in indurating stone, &c., to subject

page_text: it to a very high degree of heat, in order to make the indurating sub-
stance penetrate and permeate through the material. This, however,
has been found highly detrimental to the material under operation, and
in many cases has failed to produce the desired effect. To remedy
these evils I propose (in all cases where it is practicable), in applying
my indurating mixtures, to enclose the stone or other materials to be
operated upon in an air-tight chamber, and exhaust or partially
exhaust the same, and then allow the indurating substance, whether
hot or cold, to trickle down or flow into the chamber to fill the
vacuum, the effect of which will be that the liquid indurating substance
will readily find its way into the pores of the stone or other material,
and become incorporated therewith.
Before subjecting the materials to this process of injection they must
be heated in a chamber or oven to from fifty to sixty degrees, for the
purpose of driving out whatever moisture they may contain; and as
the process greatly increases the natural tenacity of the materials sub-
mitted to such treatment, the articles should be worked or fashioned to
their required form before being thus.operated upon.
When the materials or works of art require to be coloured, I stain
them with any suitable vegetable or mineral color by laying the same
on with a brush, and allow the color to dry before commencing the
indurating process.
Mixture No. 1. The composition of this solution is as follows:-
Fifty-six parts by weight of sulphur, dissolved, by the aid of steam heat
or dry heat, in forty-four parts of dilute vinegar or acetic acid, contain-
ing seventeen parts of acid to eight of water.
In preparing indurating mixtures to be applied to the exteriors and
interiors of buildings, whether possessing a surface of brick, stone,
cement, or plaster, I employ the following ingredients.
Mixture No. 2, contains, shellac fourteen parts by weight, seed lac
fourteen parts, coarse turpentine one part, pyroligneous spirits forty
parts.
Mixture No. 3, is composed of gutta percha dissolved in coal tar
naphtha, or other suitable solvent, in the proportion of three parts by
weight of gutta percha to eight parts of the solvent.
Mixture No., 4: The. proportions and ingredients of this mixture are

page_text: as follows:-To one bushel of limestone or chalk add twelve gallons of
water and twelve pounds of alum, half a gallon of beer grounds and
half a gallon of gall, and mix the same well together. If it is desired
to color the mixture, this may be done by adding thereto pitch, or
vegetable or mineral colors.
These solutions, when made lukewarm, may be laid on with a brush
until the surface treated will absorb no more. Works of art, blocks
of stone, and other detached porous materials of the kind specified,
may also with advantage be indurated by the use of these mixtures.
Having now described my Invention of "Improvements in the treat-
ment of natural and artificial stone, and of articles composed of porous
cements or plaster, for the purpose of hardening and coloring the
I wish it to be understood, that although I have set forth
certain definite proportions of substances to be employed in manufac-
turing my indurating mixtures, which proportions I have found to
answer satisfactorily, I do not confine myself rigidly thereto, as devia.
tions therefrom, and even substitutions, by analogous substances, for
those specified, might doubtless be made without destroying the indu-
rating property of the mixtures. What I claim therefore under the
above in part recited Letters Patent is, the means above set forth, or
any mere modification thereof, for hardening and coloring natural
and artificial stone, and articles composed of porous cements or
plaster.
In witness whereof, I, the said Barnabas Barrett, have hereunto
set my hand and seal, the Twenty-eighth day of October, in
the year of our Lord One thousand eight hundred and fifty-
BARNABAS BARRETT. (L.S.)
Witness, JOHN BENJAMIN DAINES,
of No. 15, Albert Terrace,
Stoke Newington.