IMPROVEMENTS IN COMPOUNDS ADAPTED TO BE USED FOR MARKING SURFACES, OR BLACKBOARDS, OR FOR HARD FINISH ON PLASTERING AND FOR OTHER USEFUL PURPOSES SUCH AS MORTAR FOR LAYING BRICK OR STONE
Year: 1883

page_text: LETTERS PATENT to Philip Middleton Justice of 55 & 56 Chancery Lane in
the County of Middlesex Fellow of the Institute of Patent Agents for an
Invention of IMPROVEMENTS IN COMPOUNDS ADAPTED TO BE USED FOR
MARKING SURFACES, OR BLACKBOARDS, OR FOR HARD FINISH ON PLASTERING
AND FOR OTHER USEFUL PURPOSES SUCH AS MORTAR FOR LAYING BRICK OR
STONE communicated to him from abroad by Nathaniel Frothingham Potter
of Providence State of Rhode Island one of the United States of America
PROVISIONAL SPECIFICATION left by the said Philip Middleton Justice
IN
at the Office of the Commissioners of Patents on the 18th December 1883.
PHILIP MIDDLETON JUSTICE of 55 & 56 Chancery Lane in the County of
Middlesex Fellow of the Institute of Patent Agents IMPROVEMENTS
COMPOUNDS ADAPTED TO BE USED FOR, MARKING-SURFACES OR BLACKBOARDS, OR
FOR HARD FINISH ON PLASTERING AND FOR OTHER USEFUL PURPOSES SUCH AS
MORTAR FOR LAYING BRICK OR STONE A communication to me from abroad by
Nathaniel Frothingham Potter of Providence, State of Rhode Island, one of the
United States of America
The object of this invention is the production of a compound which when "set"
shall be hard and comparatively indestructible Such compound may be used for
various useful purposes such as, for the production of surfaces for blackboards as
a finish for plaster, as a mortar for laying brick and stone. etc
When used for the production of marking surfaces or blackboards, the compound
is made from soapstone or tale alum, lime-putty, black sand silica, and mortar
black
The soapstone or tale is finely pulverized; the lime-putty is made, from burnt
lime with water mixed therewith to give it the consistency of mortar; the alum
black sand, silica, and mortar black are all pulverized or finely powdered and sifted
or screened, and all of said ingredients or substances are mixed together, to be used
for the marking surface or blackboard in about the following proportions

page_text: Soapstone or tale, one hundred pounds; alum, seven pounds; lime-putty, one
hundred pounds; black sand, one hundred pounds silica, one hundred pounds; and
mortar black, eighty eight pounds;
The above named substances in substantially the proportions given are mixed
together in a suitable receptacle sufficient water being added to render the com-
position or coating sufficiently plastic to be easily spread upon any surface, and
when it is thus ready for use, one fifth part of Plaster Paris is added thereto
The
The blackboard composition or coating may be applied as follows The common
brown mortar is applied to the laths of the wall or other surface in the usual way,
and hand floated to an even surface ready to receive the blackboard or marking
compound or coating The said coating having been previously prepared in the
manner above described is then spread upon the surface of the mortar or plaster
with a trowel or other suitable implement, to a thickness of about one eighth ()
of an inch and smoothed so as to leave an even surface, which is then brushed with
a dry brush giving a smooth black surface especially adapted to be used for
marking surfaces or blackboards without requiring any further attention
compound for marking surfaces or blackboards above described may be used for a
hard finish on plastering by leaving out of said material or composition, the black
sand silica and mortar black, with the plaster of paris If the compound is to be
used for forming a hard finish on plastering the soapstone is pulverized with alum
in the proportion of seven pounds of alum to one hundred pounds of soapstone;
one part of slaked lime or lime-putty to two parts of powdered soapstone and alum,
are mixed together, and a sufficient quantity of water stirred therewith to render
the whole, of the proper consistency to be spread upon the plastering with a trowel
in the ordinary way. The material thus formed is spread upon the face of the
plastering and rubbed over it with a trowel, or other suitable rubbing or smoothing
tool thereby producing a hard finish upon the plastering of very perfect and
enduring character If it be desired to have a very glossy or polished surface,
powdered soapstone may be applied dry or mixed with water, after which the
plastering is rubbed over with a trowel, or other suitable tool when the soapstone
has been applied in a dry state, and with a brush when applied mixed with water
There are many different shades of soap stone, so that the constructor or manufac-
turer of the compound can give the hard finish different shades as desired, by
selecting from the different colored soapstone; or if preferred, coloring matter may
be mixed with the pulverized soapstone, alum, and lime putty
The compound for marking surfaces or blackboards above described, may also be
used for mortar in laying brick, stone &c by leaving out of said material or
composition, the black sand, silica and mortar black, with the plaster of paris as
in the case of a hard finish for plaster When the compound for mortar is to be
used in laying brick and stone the ingredients are mixed together in the following
proportions, soapstone, one hundred pounds; lime putty, thirty pounds; and alum,
three pounds; sufficient water being added to bring the compound to the consistency.
of common mortar
The compound above described to be used for mortar, has great adhesive power
when dry, together with the power of resisting the disintegrating effects of heat,
and exposure to the weather. These properties are especially valuable in the
construction of chimneys, as those skilled in the art will readily understand and
appreciate. If desired, the mortar can be colored to suit the taste of the user. By
"soapstone" in this specification, reference is made to the soft magnesian mineral
technically called "talc"

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Philip Middleton Justice in the Patent Office on the 24th March
1884.
PHILIP MIDDLETON JUSTICE of 55 & 56 Chancery Lane in the County of
Middlesex Fellow of the Institute of Patent Agent IMPROVEMENTS IN COMPOUNDS
ADAPTED TO BE USED FOR MARKING SURFACES OR BLACKBOARDS OR FOR HARD
FINISH ON PLASTERING AND FOR OTHER USEFUL PURPOSES SUCH AS MORTAR FOR
"
LAYING BRICK OR STONE A communication to me from abroad by Nathaniel
Frothingham Potter of Providence State of Rhode Island one of the United States
of America
"
The object of this invention is the production of a compound which when
" set shall be hard and comparatively indestructible Such compound may
be used for various useful purposes, such as for the production of surfaces for
blackboards, as a finish for plaster, as a mortar for laying brick and stone &c.
When used for the production of marking surfaces or blackboards, the compound
is made from soapstone or talc, alum limeputty, black sand, silica, and mortar
black, The soapstone or talc is finely pulverized, the lime putty is made from
burnt lime with water mixed therewith to give it the consistency of mortar, the
alum, black sand silica and mortar black are all pulverized or finely powdered and
sifted or screened and all of said ingredients or substances are mixed together to
be used for the marking surface or blackboard in about the following proportions
Soapstone or talc, one hundred pounds; alum, seven pounds, lime putty, one
hundred pounds; black sand, one hundred pounds; silica, one hundred pounds,
and mortar black eightyeight pounds The above named substances in substan-
tially the proportions given are mixed together in a suitable receptacle, sufficient
water being added to render the composition or coating sufficiently plastic to be
easily spread upon any surface, and when it is thus ready for use, one fifth part of
plaster paris is added thereto The blackboard composition or coating may be
applied as follows. The common brown mortar is applied to the laths of the wall
or other surface in the usual way and hand floated to an even surface ready to
receive the blackboard or marking compound or coating. The said coating having
been previously prepared in the manner above described is then spread upon the
surface of the mortar or plaster with a trowel or other suitable implement to a
thickness of about one eighth (*) of an inch and smoothed so as to leave an even
surface which is then brushed with a dry brush giving a smooth black surface
especially adapted to be used for marking surfaces, or blackboards without requiring
any further attention
The compound for marking surfaces or blackboards above described may be used
for a hard finish on plastering, by leaving out of said material or compound the
black sand, silica, and mortar black, with-the plaster of paris. If the compound
is to be used for forming a hard finish on plastering, the soapstone is pulverized
with alum in the proportion of seven pounds of alum to one hundred pounds of
soapstone one part of slaked lime or lime putty to two parts of powdered soapstone
and alum are mixed together, and a sufficient quantity of water stirred therewith
to render the whole of the proper consistency to be spread upon the plastering
with a trowel in the ordinary way. The material thus formed is spread upon the
face of the plastering and rubbed over it with a trowel or other suitable rubbing
or smoothing tool, thereby producing a hard finish upon the plastering of very
perfect and enduring character. If it be desired to have a very glossy or polished
surface, powdered soapstone may be applied dry, or mixed with water after which

page_text: 1
the plastering is rubbed over with a trowel or other suitable tool when the soap-
stone has been applied in a dry state, and with a brush when applied, mixed with
water. There are many different shades of soapstone so that the constructor or
manufacturer of the compound can give the hard-finish, different shades as desired
by selecting from the different colored soapstone, or if preferred, coloring matter
may be mixed with the pulverized soapstone, alum, and lime putty The compound
for marking surfaces or blackboards above described may also be used for mortar in
laying brick, stone &c by leaving out of said material or composition the black
sand, silica, and mortar black, with the plaster paris as in the case of a hard finish
for plaster. When the compound for mortar is to be used in laying brick and
stone, the ingredients are mixed together in the following proportions; soapstone,
one hundred pounds; lime putty, thirty pounds; and alum, three pounds; sufficient
water being added to bring the composition to the consistency of common mortar.
The compound above described to be used for mortar; has great adhesive power
when dry, together with the power of resisting the disintegrating effects of heat
and exposure to the weather These properties are especially valuable in the
construction of chimneys, as those skilled in the art will readily understand and
appreciate If desired, the mortar can be colored to suit the taste of the user
By "soapstone" in this specification reference is made to the soft magnesian
mineral technically called "talc." Having thus described the invention as communi-
cated to me from abroad by my foreign correspondent what I claim and desire to
secure by Letters Patent, is.
1st A compound to be used for marking surfaces or blackboards composed of
soapstone, alum, lime putty, blacksand, silica, mortar black, and plaster paris in
the proportions substantially as above described.
2nd A compound to be used for hard finish on plastering composed of soapstone,
alum, and lime putty in the proportions substantially as above described.
3rd A compound to be used for mortar in laying brick and stone composed
of powdered scapstone, lime putty and pulverized alum, in the proportions
substantially as above described.
In Witness whereof I the said Philip Middleton Justice have hereunto set my
hand and seal this twenty fourth day of March in the year of Our Lord one
thousand eight hundred and eighty four
PHILIP M. JUSTICE (L.S.)
Signed, sealed and delivered
in the presence of
ALLEN PARRY JONES
Grad Inst P.A
56 & 55 Chancery Lane
London W C
PHILIP M. JUSTICE (L.S.)