AN IMPROVED ASPHALT COMPOUND AND APPARATUS EMPLOYED IN THE MANUFACTURE OF THE SAME, CHIEFLY DESIGNED FOR PAVING STREETS
Year: 1871

page_text: LETTERS PATENT to Joseph Ellicott Holmes, of Buckingham Street,
Strand, in the County of Middlesex, Civil and Mechanical Engi-
neer, for the Invention of "AN IMPROVED ASPHALT COMPOUND AND
APPARATUS EMPLOYED IN THE MANUFACTURE OF THE SAME, CHIEFLY DESIGNED
FOR PAVING STREETS."
Sealed the 9th January 1872, and dated the 8th November 1871.
PROVISIONAL SPECIFICATION left by the said Joseph Ellicott Holmes
at the Office of the Commissioners of Patents, with his Petition,
on the 8th November 1871.
I, JOSEPH ELLICOTT HOLMES, of Buckingham Street, Strand, in the
County of Middlesex, Civil and Mechanical Engineer, do hereby declare
the nature of the said Invention for "AN IMPROVED ASPHALT COMPOUND
AND APPARATUS EMPLOYED IN THE MANUFACTURE OF THE SAME, CHIEFLY DESIGNED
FOR PAVING STREETS," to be as follows:-
The objects of my said Invention are the production of a new
asphalt compound and the application and use of the same in the
formation of pavements and for other similar purposes.

page_text: The base of my improved compound is a substance found in great
quantities in the coal fields of Shropshire, and commonly known as
"tar rock." This rock, which contains a large proportion of mineral
tar, has not heretofore been made commercially useful or valuable, but
by subjecting it to a peculiar process and combining with it other
substances, as herein-after described, I produce a compound which
possesses great value as a paving material for roadways, footwalks,
yards, stables, and the like, and which is also highly useful as a cement
and for other similar purposes.
65
The base of my improved compound is a substance found in great
quantities in the coal fields of Shropshire, and commonly known as
tar rock." This rock, which contains a large proportion of mineral
tar, has not heretofore been made commercially useful or valuable, but
by subjecting it to a peculiar process and combining with it other
substances, as herein-after described, I produce a compound which
possesses great value as a paving material for roadways, footwalks,
yards, stables, and the like, and which is also highly useful as a cement
and for other similar purposes.
In practising my Invention I proceed as follows :
:-
First. When my improved compound is to be used as a pavement for
footways, yards, cellars, and other places not subject to violent usage or
heavy traffic, I crush and grind the aforesaid "tar rock" to a powder, and
subject it to a steady heat till the lighter or more volatile portions of
the oil in the said rock are driven off. The powder in this heated state
is spread evenly over the ground to be paved to the depth of about an
inch when made compact; it is then pressed to make it solid by heated
iron rollers drawn rapidly over it, and is rolled and cross rolled to give
the mass evenness and solidity, or it may be tamped with hot irons to
make it level and solid, and then smoothed with a finishing iron.
Secondly. For roadways where there is heavy and continuous traffic I
pulverize the said rock, and combine the same with from 50 to 100
per cent. of red iron clay, which is abundant in the vicinity of the
deposits of the aforesaid "tar rock," or with grey fire-clay found in the
mines and in contact with the said rock, or with rock chalk, unburned
lime, or plaster of Paris. Either of these substances when used is
broken, pulverized, and thoroughly and evenly mixed with the pul-
verized "tar rock," and with from five to fifteen per cent. of the crude
tar found with or surrounding the same, or I may use an equal quantity
of other natural or manufactured tar or pitch in lieu of the said crude tar.
The mass thus formed is subjected to heat as in the first instance till in
like manner the volatile or light portions of the tar are driven off. The
powdered compound is then spread upon a prepared foundation of
cement or concrete, and made smooth and even by heated rollers or
tamping irons. The thickness or depth of the material is proportioned
to the wear to which it will be subjected.

page_text: °
Thirdly. In making my improved compound I heat the mass in
revolving stills or retorts provided with condensers, and thus save a
quantity of valuable oil that by the open process of heating would be
lost, and at the same time I condense and suppress all odorous vapours,
which in populous districts would be highly offensive if allowed to
escape. I also introduce into the revolving retort an iron roller covered
with spikes or prongs to stir or agitate the material and keep it from
adhering to the surface of the retort during the beating process.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Ellicott Holmes in the Great Seal Patent
Office on the 8th May 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
ELLICOTT HOLMES, of Buckingham Street, Strand, in the County of
Middlesex, Civil and Mechanical Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of November, in the
year of our Lord One thousand eight hundred and seventy-one, in
the thirty-fifth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Joseph Ellicott Holmes, Her
special licence that I, the said Joseph Ellicott Holmes, my executors,
administrators, and assigns, or such others as I, the said Joseph Ellicott
Holmes, my executors, administrators, and 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
"AN IMPROVED ASPHALT COMPOUND AND APPARATUS EMPLOYED IN THE MANU-
PACTURE OF THE SAME, CHIEFLY DESIGNED FOR PAVING STREETS," upon the
condition (amongst others) that I, the said Joseph Ellicott Holmes, my
executors or administrators, by an instrument in writing under 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 imme-
diately after the date of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said Joseph Ellicott Holmes, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement:-
The objects of my said Invention are the production of a new
asphalt compound and the application and use of the same in the
formation of pavements and for other similar purposes.
"
The base of my improved compound is a substance found in great
quantities in the coal fields of Shropshire, and commonly known as
'tar rock." This rock, which contains a large proportion of mineral
tar, has not heretofore been made commercially useful or valuable, but
by subjecting it to a peculiar process and combining with it other
substances, as herein-after described, I produce a compound which
possesses great value as a paving material for roadways, footwalks,
yards, stables, and the like, and which is also highly useful as a
cement and for other similar purposes.
In practising my Invention I proceed as follows:-
First. When my improved compound is to be used as a pavement
for footways, yards, cellars, and other places not subject to violent usage
or heavy traffic, I crush and grind the aforesaid tar rock to a powder, and
subject it to a steady heat till the lighter or more volatile portions of
the oil in the said rock are driven off. The powder in this heated state
is spread evenly over the ground to be paved to the depth of about an
inch, and it is then pressed to make it solid by heated iron rollers drawn
rapidly over it, and is rolled and cross rolled to give the mass ovenness
and solidity, or it may be tamped with hot irons to make it level and
solid, and then smoothed with a finishing iron.
Secondly. For roadways where there is heavy and continuous traffic I
pulverize the said rock, and combine the same with from 50 to 100 per
cent. of red iron clay, which is abundant in the vicinity of the deposits
of the aforesaid "tar rock," or with grey fire-clay found in the mines
and in contact with the said rock, or with rock chalk, unburned lime, or
plaster of Paris. Either of these substances when used is broken,
pulverized, and thoroughly and evenly mixed with the pulverized "tar
rock"
and with from five to fifteen per cent. of the crude tar found
with or surrounding the same, or I may use an equal quantity of other
natural or manufactured tar or pitch in lieu of the said crude tar. The

page_text: mass thus formed is subjected to heat as in the first instance till in like
manner the volatile or light portions of the tar are driven off. The
powdered compound is then spread upon a prepared foundation of
cement or concrete and made smooth and even by heated rollers or
tamping irons. The thickness or depth of the material is proportioned
to the wear to which it will be subjected.
Third. In making my improved compound I heat the mass in revolv-
ing stills or retorts provided with condensers, and thus save a quantity
of valuable oil that by the open process of heating would be lost, and
at the same time I condense and suppress all odorous vapors, which in
populous districts would be highly offensive if allowed to escape. I
also introduce in the revolving retort an iron roller covered with spikes
or prongs to stir or agitate the material and keep it from adhering to the
surface of the retort during the heating process.
Having thus described my said Invention, and the manner of perform-
ing the same, I wish it understood that I claim,―
First. The aforesaid "tar rock" treated in the manner described, and
applied either alone or in combination with the other ingredients
specified for paving and other purposes, as herein set forth.
Second. The apparatus for making the aforesaid compound, con-
structed and operating as herein described.
TAT
JOSEPH ELLICOTT HOLMES. (L.S.)