IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL ASPHALTE, SP
Year: 1871

page_text: LETTERS PATENT to John Pender, of Arlington Street, in the County
of Middlesex, Esquire, and Martin Rae, of Uphall, in the County
of Linlithgow, North Britain, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF ARTIFICIAL ASPHALTE,
PROVISIONAL SPECIFICATION left by the said John Pender and
Martin Rae at the Office of the Commissioners of Patents, with
their Petition, on the 15th December 1871.
We, JOHN PENDER, of Arlington, Street, in the County of Middlesex,
Esquire, and MARTIN RAE, of Uphall, in the County of Linlithgow;
North Britain, do hereby declare the nature of the said Invention for
" IMPROVEMENTS. IN The ManufactuRE OF ARTIFICIAL ASPHALTE,” to be as
follows:
This Invention relates to the manufacture of an artificial asphalte from
various materials, the greater proportion of which are inexpensive and
are found in the United Kingdom, this artificial asphalte being applicable

page_text: to the same purposes as the natural asphalte, which has to be imported
from abroad at great expense. The materials we propose to employ and
their mode of preparation are as follows:-
First. Cement stone which is found in bands or nodules, which being
reduced to powder by suitable machinery is then dried upon hot plates 5
or in a furnace until all the moisture is expelled, after which it is ready
for use, or it may be stored up in air-tight casks or barrels.
Second. Limestone.
The raw limestone is ground to a powder and
dried in the same manner as the cement stone.
Third. Trap rock or "whin dykes," which are of a volcanic origin, 1
also "slag" from blast furnaces having a natural tendency to concrete
and form a dry and durable roadway, are well suited for the manufacture
of asphalte. These when broken up are ground to a powder and dried
in the same manner as already described.
Fourth. Ironstone raw from the mine is ground and prepared in the 1
same manner as already described.
Fifth. Iron ore. Ironstone calcined, one-third of clay or aluminous
earth is added and ground and dried in the same manner as already
described.
I
Sixth. Bituminous shale. The tough and elastic qualities of shale 2
render them well suited for the manufacture of asphalte, especially for
the covering of roofs and arches, or for any place where there is a
constant vibration or strain arising from the working of machinery, &c.
The bituminous shale is ground and prepared in the same manner as
already described..
From the materials enumerated above we produce six varieties of
asphalte which are applicable for various purposes being of different
degrees of density and elasticity.
.:
2
Seventh. Shale tar, which is a waste or by-product, and which is
obtained in the distillation of oil from bituminous shale, we employ as a 30
substitute for other tars in the manufacture of asphalte; and in order to
render the shale tar available for this purpose the tar must be freed from
sulphuric acid and put into a cauldron and boiled; and while boiling
about 30 lbs. of powdered bitumen to about every 112 lbs. of shale tar

page_text: must be added and well stirred and incorporated with the tar, and after
boiling for about half an hour it is then ready for use.
Having described the various materials we propose to employ and also
their mode of preparation, we will now explain our method of converting
them into asphalte.
No. 1 asphalte is composed of cement stone reduced to a powder,
together with the prepared shale tars either alone or in conjunction with
other mineral or vegetable tars, of vegetable or mineral tar and bitumen
in about the following proportions:-
The powdered cement stone is placed upon an iron plate or cylinder
sufficiently hot to boil the tar, the tar is then added to the powder and
well stirred and mixed together until the whole of the powder is dis-
colored by the tar, the bitumen is now added, the mass being kept stirred
all the while. When thoroughly incorporated it has the appearance and
consistency of moist sugar. It is then ready for use, and the prepared
materials whilst in a heated condition may then be spread upon the
concrete or other prepared surface to the required thickness, and is then
beaten down and consolidated by the use of hot iron beaters, and the
surface subsequently smoothed over with hot iron plates or "sala-
manders." The asphalte thus prepared after cooling for a few hours will
be found sufficiently hard to admit of traffic upon it.
No. 2 asphalte is composed of raw limestone reduced to a powder, of
the prepared shale tar, either alone or in conjunction with other
mineral or vegetable tars, of vegetable or mineral tars and bitumen in
about the following proportions:-

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Pender and Martin Rae in the Great Seal
Patent Office on the 15th June 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
PENDER, of Arlington Street, in the County of Middlesex, Esquire, and
MARTIN RAE, of Uphall, in the County of Linlithgow, North Britain,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of December, in the year
of our Lord One thousand eight hundred and seventy-one, in the
35th year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said John Pender and Martin Rae, Her special
license that we, the said John Pender and Martin Rae, our executors,
administrators, and assigns, or such others as we, the said John Pender
and Martin Rae, our executors, administrators, or 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 ASPHALTE,"
upon the condition (amongst others) that we, the said John Pender
and Martin Rae, our executors or administrators, by an instrument in
writing under our hands and seals, or under the hand and seal of one of
us, 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 we, the said John Pender and Martin Rae,
do hereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, that is to say :-
This Invention relates to the manufacture of artificial asphalte from
various materials, the greater proportion of which are inexpensive and are
found in the United Kingdom; this artificial asphalte being applicable

page_text: tar must be added and well stirred and incorporated with the tar, and
after boiling for about half an hour it is then ready for use.
Having described the various materials we propose to employ and also
their mode of preparation, we will now explain our method of converting
them into asphalte.
No. 1 asphalte is composed of cement stone reduced to a powder,
together with the prepared shale tar either alone or in conjunction with
other mineral or vegetable tars, of vegetable or mineral tar and bitumen,
in about the following proportions:-
The powdered cement stone is placed upon an iron plate or cylinder
sufficiently hot to boil the tar, the tar is then added to the powder and
well stirred and mixed together until the whole of the powder is dis-
coloured by the tar, the bitumen is now added, the mass being kept
stirred all the while. When thoroughly incorporated it has the appearance
and consistency of moist sugar. It is then ready for use, and the
prepared materials whilst in a heated condition may then be spread upon
the concrete or other prepared surface to the required thickness, and is
then beaten down and consolidated by the use of hot iron beaters, and
the surface subsequently smoothed over with hot iron plates or
"sala-
manders." The asphalte thus prepared after cooling for a few hours will
be found sufficiently hard to admit of traffic it.
upon
No. 2 asphalte is composed of raw limestone reduced to a powder, of
the prepared shale tar, either alone or in conjunction with other mineral
or vegetable tars, of vegetable or mineral tars and bitumen, in about the
following proportions

page_text: Having now described and particularly ascertained the nature of our
said Invention, and the manner in which the same is or may be used
or carried into effect, we would observe in conclusion that what we
consider to be novel and original, and therefore claim as the Invention
secured to us by the herein-before in part recited Letters Patent is,―
First. The production of artificial asphalte by combining cement stone,
limestone, trap rock, ironstone, calcined ironstone, or bituminous shale
with mixtures of shale tar and Trinidad or other bitumen, or mineral or
vegetable tar, or any two or more in the proportions and in the manner
herein-before described.
Second. The use of a combination of two or more of the above-
mentioned varieties of asphalte for the purposes herein-before described.
In witness whereof, I, the said John Pender, on behalf of myself
and the said Martin Rae, have to this our Specification set my
hand and seal, the Fourteenth day of June, One thousand eight
hundred and seventy-two.