A NEW OR IMPROVED MATERIAL TO BE USED FOR ROOFING OR COVERING BUILDINGS AND OTHER STRUCTURES, AND FOR SUCH OTHER PURPOSES AS THE SAME IS OR MAY BE ADDETRADED MA
Year: 1864

page_text: LETTERS PATENT to John Fielding Empson, of Birmingham, in the
County of Warwick, Manufacturer, for the Invention of "A NEW OR
IMPROVED MATERIAL TO BE USED FOR ROOFING OR COVERING BUILDINGS AND
OTHER STRUCTURES, AND FOR SUCH OTHER PURPOSES AS THE SAME IS OR MAY BE
ADDETRADED MA
"
Sealed the 20th October 1864, and dated the 9th May 1864.
PROVISIONAL SPECIFICATION left by the said John Fielding Empson
at the Office of the Commissioners of Patents, with his Petition on the
9th May 1864.
I, JOHN FIELDING EMPSON, of Birmingham, in the County of Warwick,
Manufacturer, do hereby declare the nature of the said Invention for "A
NEW OR IMPROVED MATERIAL TO BE USED FOR ROOFING OR COVERING BUILDINGS AND
OTHER STRUCTURES, AND FOR SUCH OTHER PURPOSES AS THE SAME IS OR MAY BE
APPLICABLE TO," to be as follows:-
My Invention consists of a new or improved material, manufactured in
the manner herein-after described, to be used for roofing or covering buildings
and other structures, in lieu of natural slate, and for other purposes to which
it is applicable. The said material resembles natural slate, and is both rigid
and waterproof.
In manufacturing the said new or improved material I take, by preference,
felt or thick paper or other vegetable fibre, or a mixture of vegetable fibre

page_text: with other materials, either in sheets or slabs, and I place upon the said felt
or vegetable matter pounded slate, stones, or other gritty material, and by
means of pressure (by preference bydraulic pressure) I force into and coat or
cover the said felt or vegetable matter with the said pounded slate or other
gritty material. I then take broken slate, or stone, or sand, and mix it with
asphalte or other waterproof cement or material, and I apply this mixture to
the coated surface of the felt or vegetable matter, and by pressure make the
said mixture firmly adhere thereto. I apply as many coatings of the said
mixture to the coated felt or vegetable matter as may be necessary to
render it sufficiently rigid to be applied to the roofs of buildings and for other
purposes.
Although I prefer to use felt or vegetable matter as the foundation or base
to which the slate or gritty matter is applied, and upon which it is made
firmly to adhere by pressure, yet other materials, such as cement, may be used
for that purpose.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Fielding Empson in the Great Seal Patent Office on
the 3rd November 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
FIELDING EMPSON, of Birmingham, in the County of Warwick, Manufacturer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of May, 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
John Fielding Empson, Her special licence that I, the said John Fielding
Empson, my executors, administrators, and assigns, or such others as I, the said
John Fielding Empson, my executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all times there-
after 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 "A NEW OR IMPROVED
MATERIAL TO BE USED FOR ROOFING OR COVERING BUILDINGS AND OTHER STRUCTURES,
AND FOR SUCH OTHER PURPOSES AS THE SAME IS OR MAY BE APPLICABLE TO,"
upon the condition (amongst others) that I, the said John Fielding
Empson, my executors or administrators, by an instrument in writing under

page_text: 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 John Fielding Empson, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
My Invention consists of a new or improved material, manufactured in the
ways herein-after described, to be used for roofing or covering buildings and
other structures in lieu of natural slate, and for other purposes to which it is
applicable. The said material resembles more or less natural slate, and is both
rigid and waterproof.
In manufacturing the said new or improved material, I either take thick
paper or other vegetable fibre, or a mixture of vegetable fibre with other
materials in sheets or slabs, or I take felt or other similar fibrous material,
and I treat the said sheets or slabs in the manner herein-after explained so as
to make them waterproof. I then coat or cover the surfaces of the said sheets
or slabs with gas tar, or a mixture of gas tar and pitch and asphalte, or other
bituminous substance, and I apply to the coated surfaces of the sheets or slabs,
while they are wet, pounded slate, sand, brick, or other gritty material; the
said coating making the said slate or gritty material adhere firmly to the
sheets or slabs. If necessary pressure may be applied to the slate or other
gritty matter for the purpose of making it more readily adhere to the adhesive
coating. I apply as many alternate coatings of the adliesive matter and gritty
materials as may be necessary to render the sheets or slabs sufficiently rigid to
be applied to the roofs and walls of buildings and for other purposes.
Instead of applying the coatings of tar or tarry mixture and gritty
materials to the paper separately as described, the said tar or tarry mixture
and gritty materials may be combined together before being applied to the
surfaces of the paper, or other base or foundation. Instead of applying the
gritty matter and the tar or tarry mixture singly or combined together to the
paper or other fibrous material, the tar, or tarry mixture, gritty matter, and
fibrous material may be made into a plastic state and rolled or moulded by
pressure into the required forms.
Having explained the nature of my Invention, I will proceed to describe
the manner in which the same is to be performed. In making the new or
improved material, when paper is used as the base or foundation, I take a

page_text: sheet of paper of the required size and form, and I saturate it with gas tar, or
a mixture of oil and tar spirits, as is commonly practised in the manufacture
of papier mâché, and then dry the said saturated paper in a stove or oven.
By this treatment the paper is made waterproof. After drying the paper I
dip it in gas tar, or a mixture of tar and pitch, alone or mixed with asphalte
or other bituminous substance, and while the paper is wet I apply to its
surfaces, by means of a dredging machine, or in any other convenient way, a
coating of finely pounded slate, or sand, or brick, or other gritty material, or
a mixture thereof, the adhesive matter on the said paper retaining the gritty
material and making it firmly adhere thereto; or the adhesion of the gritty
material may be made more perfect by applying pressure by means of rolls or
otherwise; the coated paper is now left to dry with or without artificial heat.
When the surfaces are sufficiently bard I repeat the coatings of tar, or tarry
mixture and gritty matter, until the sheet has attained the requisite thickness
and hardness. After each coating the paper is dried, or partially so, before
the next coating is applied. When the last coating has been applied I
thoroughly dry the coated paper or material either in a stove or by exposing it
to the air. A material is thus produced which resembles more or less natural
slate, the said material being both rigid and waterproof.. When the material
is to be used for roofing or covering buildings, holes are punched or drilled in
the sheets, or slates, or slabs, for the screws or nails for attaching them to the
roofs or walls of buildings or other structures. If extra thickness is required
I cement two or more sheets of paper together, which may be effected by
coating the said sheets with a bituminous material, and while wet submitting
them to pressure so as to make them adhere firmly together; I then apply
the alternate coatings of the tar or tarry mixture and gritty matter in the
manner before explained. The material made in the way last described is of
sufficient strength to be made into tiles, drain pipes, and other articles. When
felt or a vegetable fibre or material other than paper, is used, the process is
conducted in the manner already explained. Instead of first applying the
adhesive mixture to the surface of the paper or other base, and after-
wards the gritty matter, the adhesive mixture and gritty matter may
be combined together before being applied to the paper or other fibrous
material.
When I use a mixture of gas tar, pitch, and asphalte, or other bituminous
matter, I prefer to use a mixture composed of about seven parts by
weight of gas tar, two parts by weight of pitch, and one part by weight
of asphalte or other bituminous material. When I use tar and pitch
only I employ six parts by weight of tar to one part by weight of pitch.

page_text: When I carry my Invention into effect by making the adhesive material and
gritty matter into a plastic state, and give the plastic composition the required
form either by rolls or by pressure in moulds or dies I proceed as follows:-I
melt in a furnace gas tar, pitch, and asphalte, in the proportions already stated,
and when the mixture has been thoroughly incorporated I run it into another
furnace sufficiently heated to maintain the mixture in a liquid condition. I
now add to the adhesive mixture pounded slate, or brick, or sand, or other
gritty matters, or a mixture thereof, or sawdust, so as to form a thick paste,
and in order to bind the mixture together I further add cut hay or chaff,
waste flax, or cotton, or other fibrous material. The quantity of vegetable
fibre I employ varies with the nature of the vegetable matter employed and
the stiffness to be given to the composition; but I have found that a quantity
of vegetable fibre equal in weight to about one-eighth of the whole weight of
the composition answers very well. I mix the whole together by using in
the furnace, in which the mixture is contained, a revolving shaft provided with
an endless screw or a series of screw-like blades or arms. By the rotation of
the said revolving screw or screw blades the mixture may be thoroughly
incorporated so as to form a plastic mass, and when the plastic mixture is
ready to be used it may be forced, by the motion of the said screw or screw
blades, through an aperture in the front of the furnace on to an endless web
or band, by which web or band the plastic mixture is conveyed between a
pair of rolls, by which it is pressed into a hard and compact sheet. After
being pressed between the rolls, the material is carried forward on a moveable
frame and cut into the sizes required in the same may as paper is usually cut.
Instead of passing the plastic mixture between a pair of rolls in a continuous
sheet, it may be run or forced by pressure into suitable moulds or dies of the
required form and size.
The material when made into sheets in the manner described may be used
for roofing and for other purposes, or the sheets may be cut into slates, tiles,
or other forms, and when run or forced by pressure into moulds or dies, the
material may be applied to the manufacture of drain pipes, flower pots, vases,
and other vessels and articles which are now made of terra cotta. 'When I
wish to make the artificial slates, or tiles, or other articles, of different colours,
I either mix the colouring matter with the gritty materials in making the
plastic mixture, or I coat or colour the finished material or articles in
the same way as japanners colour tea trays, but other means may be
adopted.
Having now described the nature of my Invention, and the manner in
which the same is to be performed, I wish it to be understood that I do not

page_text: limit myself to the precise details herein described, as the same may be varied
without departing from the nature of my Invention.
But I claim as my Invention a 'new or improved material to be used for
roofing or covering buildings and other structures, and for such other purposes
as the same is or may be applicable to, manufactured in the ways herein-before
described, that is to say,, a material consisting, essentially of a base or
foundation of paper, or other fibrous mixture or material, upon the surfaces
of which pounded slate or other gritty material is made to adhere by means
of tar, or pitch, or a mixture of tar, pitch, and asphalte, or other bituminous
matter; or a material consisting essentially of a mixture of gas tar, pitch, and
asphalte, or other bituminous matter, combined with hay or chaff, waste flax,
or cotton, or other fibrous or binding material, the said mixture being
made into a plastic mass, and formed into sheets or slabs, or moulded or
pressed in dies.
In witness whereof, I, the said John Fielding Empson, have hereunto
set my hand and seal, this Second day of November, in the year.
of our Lord One thousand eight hundred and sixty-four.
Witness,
RICHARD SKERRETT,
Clerk to George Shaw,
JOHN FIELDING EMPSON. (L.S.)
Birmingham.