IMPROVEMENTS IN THE MANUFACTURE' OF ARTIFICIAL ASPHALT ROCK
Year: 1871

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London, for
the Invention of "IMPROVEMENTS IN THE MANUFACTURE' OF ARTIFICIAL
ASPHALT ROCK." - A communication from abroad by Archibald
Burnett Vandemark and Samuel Register Scharf, both of Jersey
City, New Jersey, United States of America.
1
COMPLETE SPECIFICATION filed by the said William Robert Lake at
the Office of the Commissioners of Patents, with his. Petition and
Declaration, on the 28th September 1871, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852.
•
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, 'WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.

page_text: Majesty to grant unto me, my executors, administrators, and assigns
Her Royal Letters Patent for the same, and have made solemn Declara-
tion that it has been communicated to me from abroad by Archibald
Burnett Vandemark and Samuel Register Scharf, both of Jersey City,
New Jersey, United States of America.
NOW KNOW YE, that I, the said William Robert Lake, do hereby
declare that the following Complete Specification, under my hand and
seal, fully describes and ascertains the nature of the said Invention,
and in what manner the same is to be performed, in and by the following
statement:—
The object of this Invention is to impregnate calcareous substances
with bitumen, thereby producing an artificial asphalt rock which can
be used with advantage for pavements and for roofing, which shall be
impervious to water, unaffected by the heats of summer or the frosts of
winter, fine grained, homogenous, tough, and durable.
The said Invention consists in the combination, mixture, and appliance
of the constituent parts, viz., bitumen or its chemical equivalent,
paraffine oil or its chemical equivalent, and a calcareous substance such
as calcareous rock, lime, or carbonate of lime, which constituents when
properly mixed together compose the artificial asphalt rock.
The above-named ingredients are mixed together in about the
following proportion, viz., bitumen or asphaltum of commerce from
50 to 95 parts, paraffine oil or other heavy hydrocarbon liquid from
50 to 5 parts. These ingredients are placed in a proper vessel where
they are heated to a temperature of above two hundred and below a
three hundred degrees, or just below that temperature which would be
destructive to the bitumen or which would cause the escape of essential
oils from the said bitumen. While being heated the mass is constantly;
agitated until the bitumen and oil become thoroughly mixed and take
the appearance of a thick liquid of a homogenous character. At the
same time a quantity of calcareous stone or other calcareous substance,
such as limestone, chalk, or marl, which has been pulverized by suitable
means, is heated in a separate vessel until the same is freed from all
moisture. This calcareous powder is then mixed with the compound
of bitumen and oil in about the following proportion :-Calcareous'
powder from 60 to 85 parts, compound of bitumen and oil from 40 to 15
parts. Both the bituminous compound and the calcareous powder-are.

page_text: placed in a heated state in a suitable vessel, where the same are heated
and agitated until the calcareous powder becomes thoroughly impreg
nated with the bituminous compound, and all the ingredients are united
in a homogenous mass.
When this composition is to be used for the pavement of streets, for
side walks, alleys, or.. paths, a foundation, is first made of broken stones
evenly rolled or of cement or any other sort of foundation which is firm
and tolerably uniform, and upon this foundation the above described
composition is. spread, hot, and then, rolled down smoothly and solidly
as it hardens.
1 8
The thickness or depth of the, composition.laid, down depends upon
the nature of the street or walk, a layer of one-half inch being sufficient
for, narrow. pathways, and a layer of two inches or more in thickness
for heavily travelled streets. When said composition is to bo used
for roofing purposes the proportion between the calcareous powder
and the bituminous compound may be changed, the said ingredients
being mixed together in about equal-parts. The preparation- is then
poured hot upon the roof in a thin sheet, and suitably rolled while
hardening.
F.
.
The proportion of oil in the bituminous compound is governed by.
different climates and also by the nature of the bitumen used in the
compound. For cold climates more oil is used than for hot climates.
The pavements which have heretofore been made of sand, gravel,
broken stone, and, coal tar or asphaltum have been subject to defects
in wear by reason of the non-union or imperfect union of the stony
portions with the cementing or binding portions of the compound,
whereby, under the influence of the elements and the abrasion of travel,
the stone, gravel, or sand works out and becomes separated from the
remainder of the mass, which then becomes rough or rutted and in the
way of early destruction..
In the artificial asphalt rock prepared according to the above
description the calcareous substance becomes thoroughly impregnated
with the bituminous compound forming a homogenous mass which when
properly laid presents a smooth surface and continues smooth by wear,
and furthermore a pavement prepared from this asphalt rock is exceed-
ingly tough, resisting fracture admirably, and from the character of its.
constituent parts and their manner of union will resist equally well
extreme heat or cold.
1

page_text: Having thus fully described the said Invention as communicated to
me by my foreign correspondents, and shown how the same may be
conveniently and advantageously carried into practice, I claim,-
First. An artificial asphalt rock made substantially in the manner
herein described.
Second. Combining bitumen and paraffine oil or their chemical equi-
valents and calcareous substances substantially in the manner and about
in the proportions herein set forth.
In witness whereof, I, the said William Robert Lake, have here.
unto set my hand and seal, this Twenty-eighth day of September:
in the year of our Lord One thousand eight hundred and seventy-
one.
Witness,
W. J. LOWE.
WILL, ROB. LAKE. (L.S.)