AN IMPROVED SYSTEM OF PAVING BY THE EMPLOYMENT OF NATURAL OR ARTIFICIAL BITUMEN COMBINED WITH IRON ORE, AND FOR AN IMPROVED PROCESS OF MANUFACTURING THE ARTIFICIAL BITUMEN
Year: 1868

page_text: LETTERS PATENT to Frederic Barnett, of 164, Rue de Rivoli, Paris, in
the Empire of France, for the Invention of "AN IMPROVED SYSTEM OF
PAVING BY THE EMPLOYMENT OF NATURAL OR ARTIFICIAL BITUMEN COMBINED
WITH IRON ORE, AND FOR AN IMPROVED PROCESS OF MANUFACTURING THE
ARTIFICIAL BITUMEN."
Sealed the 6th April 1869, and dated the 10th October 1868.
PROVISIONAL SPECIFICATION left by the said Frederic Barnett at
the Office of the Commissioners of Patents, with his Petition, on
the 10th October 1868.
I, FREDERIC BARNETT, of 164, Rue de Rivoli, Paris, in the Empire of
France, do hereby declare the nature of the said Invention for "A
IMPROVED SYSTEM OF PAVING BY THE EMPLOYMENT OF NATURAL OR ARTIFICIAL
BITUMEN COMBINED WITH IRON ORE, AND FOR AN IMPROVED PROCESS OF MANU-
FACTURING THE ARTIFICIAL BITUMEN," to be as follows:-
It is found that the carriages in large towns circulating over the
ordinary granite paved roads cause so much confusion and noise that
without taking into consideration their expense, they become dis-

page_text: agreeable and actually cause an important impediment to commerce,
either in the shops, banks, professional & trade offices, or elsewhere,
where quiet is desirable for thinking, speaking, hearing, or being heard;
but where to attain a diminution of noise the macadamised principle has
been adopted the stone employed is rapidly crushed into powder, which
during dry periods is drifted about to the inconvenience of persons and
prejudice of merchandise, and during wet seasons is converted into mud.
These inconveniences I propose remedying by the manufacture of a
material suitable for forming roads and pavements of an economical,
durable, and cleanly nature, possessing an even surface to ensure a com-
paratively quiet circulation, being at the same time sufficiently rugose
to prevent the cattle from slipping. And to attain this end I compose by
the following process a material which I call "iron asphalte":-1°. The
compose of forty-five parts of natural asphalte (or as it may suit
me artificial) for preference; when I employ the natural asphalte it is
that which is found in the quarries at Travers (Switzerland). 2°. Of
forty-five parts of pulverised iron ore, or better still, the natural
sesquioxide of iron, which can be collected in inexhaustible quan-
tities already reduced reduced to powder on the sea coast in the precincts
of Vesuvius, and ten parts of mineral tar.
Thus, of natural or artificial bitumen
parts 45

page_text: prepared in this manner:-Firstly, the ground must be lowered about
five (5) inches, levelled, and then covered with three or more inches
of cement, thus composed,-
well compressed and levelled before hardening. When hard a layer of
about an inch thick of the iron asphalte is then spread over the cement,
well compressed, and smoothly levelled. When this first is thoroughly
cooled an equal quantity of the iron asphalte is superposed.
In laying down the asphalte thus in two layers the quantity of air
Finally, while still hot the whole
bubbles is notably diminished.
surface is liberally dusted with the powdered iron ore, over which a
heavy heated iron roller is passed. The chemical combination which
ensues renders the surface much less slippery..
Of
The following method of composing an artificial bitumen can be
applied in the same way as above described. I place in a strong iron:
cauldron successive layers of powdered limestone and pitch.
the first I employ, say, half a ton to five cwts. of the second. The
upper part of this cauldron is then hermetically closed and half a cwt.
of mineral tar is therein injected; the cauldron is then heated by the
furnace beneath it, and then the whole is kept stirred by similar
machinery as that above described, and the ingredients being heated to
ebulition the whole will chemically combine under the influence of the
mineral tar, the vapor of which in its turn escapes and becomes liquified
in a condenser. The mass is then drawn off into moulds, & when
cooling it forms cakes of the desired size, which when thus prepared
are employed as I have described the way of employing the iron asphalto
when made of the natural asphalte.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Pate,
filed by the said Frederic Barnett in the Great Seal Patent Office
on the 7th April 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERI
BARNETT, of 164, -Rue de Rivoli, Paris, in the Empire of Fraifèè,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Tenth day of October, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Frederic Barnett, Her special licence that
I, the said Frederic Barnett, my executors, administrators, and assigns,
or such others as I, the said Frederic Barnett, my executors, adminis-
trators, 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 SYSTEM OF
PAVING BY THE EMPLOYMENT OF NATURAL OR ARTIFICIAL BITUMEN COMBINED
WITH IRON ORE, AND FOR AN IMPROVED PROCESS OF MANUFACTURING THE
ARTIFICIAL BITUMEN," upon the condition (amongst others) that I, the
said Frederic Barnett, my executors or administrators, by an instru-
ment 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 immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Frederic Barnett, 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:-
That the carriages in large towns circulating over the ordinary granite
paved roads cause so much confusion and noise that, without taking
into consideration their expense they become disagreeable and actually
cause an important impediment to commerce, either in the shops, banks,

page_text: thinking, speaking, hearing, or being heard; but where to attain a
diminution of noise the macadamized principle has been adopted the
stone employed is rapidly crushed into powder, which during dry
periods is drifted about to the inconvenience of persons and prejudice
of merchandise, and during wet seasons is converted into mud. These
inconveniences I propose remedying by the manufacture of a material
suitable for forming roads and pavements of an economical, durable,
and cleanly nature, possessing an even surface to ensure a comparatively
quiet circulation, being at the same time sufficiently rugose to prevent
the cattle from slipping. And to attain this end I compose by the
following process a material I call "iron asphalt," 1st, the same I
compose of forty-five parts of natural asphalt (or as it may suit me
artificial). For preference when I employ the natural asphalt it is that
which is found in the quarries at Travers (Switzerland). 2dly, of forty-
five parts of pulverized iron ore, or better still the natural sesquioxide
af iron, which can be collected in inexhaustible quantities already
reduced to powder on the sea coast in the precincts of Vesuvius, and
ten parts of mineral tar. Thus, -
-
The natural asphalt must be broken into small pieces and then ground in
mills (composed of two or more huge circular iron bodies turning on an
extended and common axle set in motion by steam or other sufficient
power), and thus reduced to a powder, which is subsequently sifted;
the iron ore undergoing the same treatment with a similar result. To
prepare this composition ten parts of mineral tar are introduced into
an iron cauldron suspended above a heated furnace, to which are added
forty-five parts of pulverised bitumen, these being left till thoroughly
fused, and then forty-five parts of the powdered iron ore are added,
the whole being continually stirred by agitators kept in rotatory
motion.
When the composition is rendered homogene it is employed as
follows: The places intended to be covered with asphalt must be
prepared in this manner, firstly, the ground must be lowered about

page_text: Sufficient water must be added to slake and bind it. This layer must
be well compressed and levelled before hardening. When hard a layer
of about an inch thick of the iron asphalt is then spread over the
cement, well compressed, and smoothly levelled. When the first is
thoroughly cooled an equal quantity of the iron asphalt is superposed.
In laying down the asphalt thus in two layers the quantity of air
bubbles is notably diminished. Finally, while still hot the whole
surface is liberally dusted with the powdered iron ore, over which a
heavy heated iron roller is passed; the chemical combination which
ensues renders the surface much less slippery.
The following method of composing an artificial bitumen can be
applied in the same way as above described:-I place in a strong iron
cauldron successive layers of powdered limestone and pitch; of the first
I employ, say, half a ton to five hundredweight of the second; the
upper part of the cauldron is then hermetically closed, and half a
hundredweight of mineral tar is therein injected; the cauldron is then
heated by the furnace beneath it, and then the whole is kept stirred by
similar machinery as that above described, and the ingredients being
heated to ebullition the whole will chemically combine under the
influence of the mineral tar, the vapor of which in its turn escapes
and becomes liquified in a condenser. The mass is then drawn off into
moulds, and when cooling forms cakes of the desired size, which when
thus prepared are employed as I have described the way of employing
the iron asphalt when made with the natural asphalt.
In witness whereof, I, the said Frederic Barnett, have hereunto
set my hand and seal, this Fifth day of April, in the year
of our Lord Eighteen hundred and sixty-nine.
FREDERIC BARNETT. (L.S.)