An Improved Method of Hardening and Preparing Soft Porous Stone for Enamelling and other purposes
Year: 1890

page_text: Date of Application, 4th Mar., 1890
Complete Specification Left, 4th Nov., 1890-Accepted, 20th Dec., 1890
PROVISIONAL SPECIFICATION.
An Improved Method of Hardening and Preparing Soft Porous Stone
for Enamelling and other purposes.
WILLIAM THOMPSON SIER Eves Well Park Maindee Newport Mon. do hereby
declare the nature of this invention to be as follows:-
An improved method for toughening and hardening soft porous stone, viz. Bath-
stone, Caen, Painswick, Ancaster, Bradford and all other oolite formation of soft
& porous stones and consists in submitting, the above or any of the above to a
bath of silica or flint and boiled in the liquid silica of a registered strength 1.175
for eight hours, it is then taken out and placed in a drying stove thoroughly
prepared to receive the enamel and to be applied to the making of chimney pieces
and all other architectural work.
Dated this 97th day of February 1890
COMPLETE SPECIFICATION.
An Improved Method of Hardening and Preparing Soft Porous Stone
for Enamelling and other purposes.
WILLIAM THOMPSON SIER Eves Well Park, Maindee, Newport, Mon.
Sculptor. I 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 following statement:-
An improved method for toughening & hardening soft, porous stone viz. Bath-
stone, Beer stone, Caen stone, Painswick, Ancaster, Bradford and all other oolite
& soft porous stones and consists in submitting the above or any of the above to
a bath of silica or flint and boiled in the liquid silica of a registered strength
1175, for eight hours "in a closed boiler with safety valve attached," it is then taken
out & placed in a drying stove registered heat 200 Fahrenheit, it is then boiled
with ground alabaster and lime water, it is then ready to receive the enamel and
to be used for chimney pieces and other architectural work. Or if the stone is
allowed to soak for eight days instead of boiling it will answer with the same
treatment as before described. The following is the way I prepare a "silica of soda
or flint bath." The silica of soda is diluted with clean water reducing the strength
of 1175 (hydrometre) and pouring the same into the bath or closed boiler fitted
with safety valve into which has been placed the stone, dried, sawn and worked.
It is then boiled for 8 hours or at the rate of 4 hours to every inch in thickness
of the stone under preparation. If saturated in an open tank with the silica of
soda at the rate of 4 days to every inch in thickness of stone under operation it
will answer the same purpose. I prefer the boiling process. The next process is
to place the stone in a hot stove for ten hours the heat to be kept at 200 Fahrenheit
which will prevent the stone from salting.
The next process is to coat over the dried stone with alabastine or a coating
of distemper colour. I prefer the alabastine, a preparation made by the Church
Manufacturing Co. 127 Pomeroy Street Hatcham London. This process fills the
pores of the stones and prevents them absorbing too much of the stoving varnish
"and will only be used for enamelled work."
My treatment of stones exposed to the weather after boiling and drying them,
must be finished off in the usual way with rasps etc. It will then be placed into a
"bath of lime water" mixed with powdered alabaster and boiled for one hour,
rp'. 011

page_text: This last process is a preventative for salting which the heating process may not,
in all cases prevent. The way to obtain the lime water. Take 28 lbs. fresh lime
in lumps, 7 lbs. of powdered alabaster placed into a cask and 30 gallons of water
added.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is :-
:―
(1) The preparation of soft stones for enamelling purposes.
(2) The preparation of soft stones, making them impervious to the weather.
Dated the 1
1000
WILLIAM THOMPSON SIER.