IMPROVEMENTS IN THE TREATMENT OF ASPHALTE AND IN THE APPLICATION OF THE SAME TO PAVEMENTS AND OTHER USEFUL PURPOSES.
Year: 1873

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of
"IMPROVEMENTS IN THE TREATMENT OF ASPHALTE AND IN THE APPLICATION
OF THE SAME TO PAVEMENTS AND OTHER USEFUL PURPOSES.”. A communi-
cation from abroad by Leon Malo and Theodore Robin, of Paris, in
the Republic of France.
Scaled the 30th December 1873, and dated the 9th October 1873.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition, on
the 9th October 1873.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
3 of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE TREATMENT OF ASPHALTE AND IN THE
APPLICATION OF THE SAME TO PAVEMENTS AND OTHER USEFUL PURPOSES," a com-
munication to me from abroad by Leon Malo and Theodore Robin, of
Paris, in the Republic of France, to be as follows:―
This Invention consists in the manufacture of blocks, tiles, or slabs

page_text: of compressed and moulded asphalte, and in the application of such
compressed blocks, tiles, or slabs to the covering of the surfaces of roads,
streets, and other places subjected to traffic, or to other purposes where
compressed asphalte is capable of being employed.
The asphalte having been reduced to a fine state of division is com-
pressed or solidified by pressure, or remaining whilst in a heated or cold
state in moulds of any required form.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Scal Patent
Office on the 2nd April 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
-HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of October, in the year of
our Lord One thousand eight hundred and seventy-three, in the 37th
give
year of Her reign, did, for Herself, Her heirs and successors,
and grant unto me, the said John Henry Johnson, Her special license
that I, the said John Henry Johnson, my executors, administrators,
and assigns, or such others as I, the said John Henry Johnson,
my 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 TREATMENT OF ASPHALTE and in the APPLICATION OF THE SAME To Pave-
*MENTS AND OTHER USEFUL PURPOSES,” a communication to me from abroad by
Leon Malo and Theodore Robin, of Paris, in the Republic of France,
upon the condition (amongst others) that I, the said John Henry
Johnson, my exccutors or administrators, by an instrument in writing,

page_text: under my hand and seal, 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 Henry Johnson, do hereby
declare the nature of the said Invention, and in what, manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawings and to the letters and figures, marked thereon, that is to
say:
The said Invention relates to an improved mode of treating asphalte
and of applying the same to pavements and other purposes for, which
compressed asphalte is capable of being employed..
According to the ordinary method the rock asphalte is first pulverised
and the powder thus formed is then heated and spread over the bottom
or foundation of the roadway and highly compressed whilst still in its
heated condition by means of stampers or rollers.
Now this Invention consists in previously compressing-the asphalte in
moulds into the form of blocks, tiles, or slabs, of slight thickness which
when placed in juxtaposition on a layer of concrete or other solid bottom
or foundation, constituto a similar road with the exception of the joints
to the ordinary compressed asphalted roads.
This improved process of compressing in moulds the rock asphalte
reduced to powder imparts peculiar qualities to the products obtained,
which qualities constitute the blocks, tiles, or slabs, entirely new com-
mercial products admitting of the paving of roads; streets, and other
surfaces being effected under conditions different in practice from those
of any of the present systems, whilst yielding as a result an elastic
road possessing properties similar to those which can only at present
be obtained by the existing processes applied direct on the spot.
In carrying out this Invention the natural rock asphalte is taken in
the condition in which it leaves the mine, and pulverised in the ordinary
or other suitable apparatus; it is then subjected, without heating it, to a
sufficient pressure in moulds to form blocks, tiles, or slabs of compressed
asphalte, which when conveyed to the place where they are required to

page_text: :
be used and laid in juxtaposition produce a road similar (with the.
exception of the joints) to the ordinary compressed ashphalted roads.
These processes therefore differ essentially both in their principles and in'
the mode of carrying them out from the system at present in use. They
present moreover the following important advantages, videlicet :-
First. The heating of the powder is dispensed with, which operation is
both burdensome and prejudicial to the durability of the works.
Secondly. The whole of the apparatus, such for example, as stampers,
rollers, ordinarily employed in applying the asphalte, as also special
workmen are rendered unnecessary, the operation simply consisting
in placing the blocks, tiles, or slabs side by side upon the concrete
bottom or foundation of the road, which operation may be performed by
an ordinary labourer, whence it follows that the compressed asphalte
may be employed in the smallest localities after the manner of simple
brick paving.
Thirdly. The blocks, tiles, or slabs, being all subjected to a regular
and uniform degree of compression which is previously calculated, the
asphalted surface is not liable to the deformations resulting from the
inequalities of compression in the existing system.
Fourthly. The maintenance of the asphalted surfaces is extremely
simplified, as when any part becomes deteriorated it is simply required
to remove the injured blocks, tiles, or slabs, and to substitute for them
others in good condition without the necessity of employing any special
tool or apparatus or special workmen.
Fifthly. As the blocks, tiles, or slabs are laid in a cold state it becomes
unnecessary to wait, as in the case at present, until the concrete is dry
before applying the asphalte, which advantage is of considerable im-
portance in works on the public ways, and directly the blocks, tiles, or
slabs are laid the road may be thrown open for traffic.
Having now described and particularly ascertained the nature of the
said Invention and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider to
be novel and original, and therefore claim as the Invention secured to me
by the herein-before in part recited Letters Patent is, the employment of
asphalte in the form of blocks, tiles, or slabs produced by compressing
:
E

page_text: such asphalte in moulds in the manner and for the purposes herein-before
described.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, the Thirty-first day of
March, One thousand eight hundred and seventy-four.