IMPROVEMENTS IN ROADWAYS, PAVEMENTS, AND OTHER LIKE SURFACES."
Year: 1881

page_text: LETTERS PATENT to James Herd, of Birmingham, in the County of Warwick,
Gentleman, for an Invention of "IMPROVEMENTS IN ROADWAYS, PAVEMENTS,
AND OTHER LIKE SURFACES."
PROVISIONAL SPECIFICATION left by the said James Herd at the Office
of the Commissioners of Patents on the 3rd June 1881.
JAMES HERD, of Birmingham, in the County of Warwick, Gentleman. "IMPROVE-
MENTS IN ROADWAYS, PAVEMENTS. AND OTHER LIKE SURFACES.".
My Invention has for its object the production of roadways, pavements, and
other like surfaces, which, while possessed generally of the quality of asphalte
surfaces, at the same time afford sufficient foothold for horse or other traffic.
I will describe my Invention in connection with a roadway.
I form the roadway by the use of blocks or setts made in the manner herein
after described, the said blocks or setts being laid as ordinary granite or other
paving blocks, excepting that they are connected together as herein after explained.
In making one of the said blocks I cast or otherwise form an iron or inetallic
grating, the parts where the bars of the grating intersect or cross one another being
on the same level but standing above the plane in which the other portions of the
grating are situated.
I place the said grating with the projecting parts downwards in a mould
consisting of a box open at top, the said box having at bottom slightly. sunken
parts or depressions corresponding to the projecting parts of the grating, into which
depressions the projecting parts of the grating enter when the said grating is placed
on the bottom of the mould. I beat the grating before placing it in the mould.
I pour into the mould melted asphalte or pitch, a sufficient quantity of asphalte
or pitch being poured into the mould to cover or partially cover the grating, which
thus becomes nearly embedded therein, the projecting parts of the grating engaged
in the depressions on the bottom of the mould receiving no coating of asphalte or
pitch. The mould is then partially filled with a mixture of limestone, basalt, or
other earthy material mixed with melted asphalte or pitch, or a solution of asphalte
or pitch in petroline, the remaining portion of the mould being filled with concrete
Price G1

page_text: I prefer to heat the said materials before introducing them into the mould, and
after the mould has been filled I apply pressure so as to consolidate the contents of
the mould. The contents of the mould cooling together, uniforın contraction takes
place, and there is no injurious strain in any part of the block thus formed. After
the materials have cooled the block formed falls from the mould by simple inversion
of the mould.
Where great strength is required in the blocks, as, for example, where they are
employed in covering subways or other cavities, I give the required strength by
the employment of strips of hoop iron or the like embedded in the concrete near
the base of the block, the ends of the strips being turned down to give them a
greater hold on the concrete.
After the blocks have been laid in the usual way I connect them by filling the
interstices between them with melted asphalte or pitch, or a solution of asphalte or
pitch in petroline. Where it is inconvenient or is for any reason undesirable to
employ heat in the way herein before described in the manufacture of the blocks,
I coat the metallic grating with a solution of asphalte or pitch in petroline. By
these means the melted asphalte or pitch is made to attach itself as effectually to
the cold grating as when heat is employed.
A roadway constructed according to my Invention consists of blocks composed
mainly of concrete or other earthy material, the said blocks being faced with
asphalte or other like material, and having metallic projections, which give sufficient
foothold for beasts of burden and for other purposes.
Although I prefer to employ asphalte or pitch for facing the blocks, yet I do not
limit myself thereto, as any other substance or composition having similar physical
properties may be employed instead of asphalte or pitch.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James Herd in the Great Seal Patent Office on the 30th November
1881.
JAMES HERD, of Birmingham, in the County of Warwick, Gentleman. "IMPROVE-
MENTS IN ROADWAYS, PAVEMENTS, AND OTHER LIKE SURFACES."
My Invention has for its object the production of roadways, pavements, and
other like surfaces, which, while possessed generally of the quality of asphalte
surfaces, at the same time afford sufficient foothold for horse or other traffic.
I will describe my Invention in connection with a roadway.
I form the roadway by the use of blocks or setts made in the manner hereinafter
described, the said blocks or setts being laid as ordinary granito or other paving
blocks, excepting that they are connected together as hereinafter explained.
In making one of the said blocks I cast or otherwise forin an iron or metallic
grating, the parts where the bars of the grating intersect or cross one another being
on the same level but standing above the plane in which the other portions of the
grating are situated.
I place the said grating with the projecting parts downwards in a mould
consisting of a box open at top, the said box having at bottom slightly sunken
parts or depressions corresponding to the projecting parts of the grating, into
which depressions the projecting parts of the grating enter when the said grating
is placed on the bottom of the mould. I heat the grating before placing it in the
mould. I pour into the mould melted asphalte or pitch, a sufficient quantity of
asphalte or pitch being poured into the mould to cover or partially cover the
grating, which thus becomes nearly embedded therein, the projecting parts of the
grating engaged in the depressions on the bettom of the mould receiving no coating
of asphalte or pitch.
The mould is then partially filled with a mixture of limestone, basalt, or other
earthy material mixed with melted asphalte or pitch, or a solution of asphalte
or pitch in petroline, the remaining portion of the mould being filled with concrete.
prefer to heat the said materials before introducing them into the mould,
and after the mould has been filled I apply pressure so as to consolidate the
contents of the mould. The contents of the mould cooling together, uniform
contraction takes place, and there is no injurious strain in any part of tho block
thus formed. After the materials have cooled the block formed falls from the
mould by simple inversion of the mould.
Where great strength is required in the blocks, as, for example, where they are
employed in covering subways or other cavities, I give the required strength by
the employment of strips of hoop iron or bais of iron embedded in the concrete near
the base of the block, the ends of the strips being turned down to give them a
greater hold on the concrete.
After the blocks have been laid in the usual way I connect them by filling the
interstices between them with melted asphalte or pitch, or a solution of asphalte
or pitch in petroline. Where it is inconvenient or is for any reason undesirable
to employ heat in the way herein before described in the manufacture of the blocks,
I coat the metallic grating with a solution of asphalte or pitch in petroline. By
these means the melted asphalte or pitch is made to attach itself as effectually to
the cold grating as when heat is employed.
I will now proceed to describe with reference to the accompanying Drawing the
manner in which my Invention is to be performed.
Figure 1 represents in vertical section, and Figure 2 in plan (with a portion
of the asphalte removed) a paving block or sett constructed according to my
Invention.

page_text: a, a, is the iron or metallic grating composed of a series of inverted arch shaped
bars crossing one another at right angles, the arches of the said bars being joined
together at their abutments. The abutments of the inverted arches or the inter-
secting parts of the bars of the grating project above the other parts and constitute
cruciform (or other shaped) studs marked b (best seen in Figure 2), by which the
necessary roughness for foothold is given to the roadway surface of the block or
sett. The projecting parts or studs are generally made to project about one
sixteenth of an inch above the asphalte surface in which they are fixed, so that the
tyres of wheels of ordinary dimensions roll upon them without coming in contact
with the asphalte. The studs b may either be made in one piece with the grating a
or separately, and attached at the intersections of the grating. I do not limit
myself to the use of gratings composed of arch shaped crossing bars as represented
in the Drawing, as the gratings may be made of flat or other shaped bars.
The asphalte or pitch in which the grating a is embedded, and which constitutes
the facing of the block, is marked c, and the mass of concrete or the other material
described to which the embedded grating is secured is marked d.
A series of the blocks or setts, Figures 1 and 2, being cemented together side by
side, as herein after described, forms the roadway, pavement, or other surface.
In making the block or sett, Figures 1 and 2, I proceed as follows:-I take a
mould open at top provided with a bottom plate, and having a depth, say, of about
six inches, or equal to the thickness of the paving block to be made. The bottom
plate of the mould is provided with depressions arranged to correspond with the
studs b formed on or attached to the grating a. The mould is so constructed that
the sides may be detached for readily removing the finished block from the mould.
Having heated the grating a I place it in the mould in an inverted position, the
studs bengaging with the depressions described in the bottom plate of the mould,
and I pour into the mould sufficient melted asphalte to cover the grating a, so as
to embed it in the asphalte or pitch. While the layer of asphalte or pitch in
which the grating a is embedded remains in a liquid or soft or plastic state I press
into the mould broken bricks, limestone, or other material, also heated so as to
cause them to firmly unite with the layer of asphalte or pitch described. The
broken materials described may be used alone or mixed with asphalte or pitch, or
with a solution thereof. After the earthy materials have properly consolidated,
the remainder of the mould is filled with concrete, which adhering to that portion
of the broken material not covered with the asphalte or bituminous substance, on
setting and hardening completes the improved paving block. The said block is
removed from the mould, and has the form represented in Figures 1 and 2.
In using the blocks or setts thus made they are placed side by side on the
previously prepared substratum of the road or street, and the interstices or spaces
between the blocks filled with melted asphalte, so as to give a continuous surface
to the roadway.
In order to facilitate the cementing of the blocks together their upper edges may
bo chamfered, as seen at f, Figure 1, so that when the blocks are arranged side by
side an angular groove is formed between the adjacent blocks, into which groove
the cement is poured.
The shape and size of the paving blocks or setts may be varied to suit tho
particular purposes to which they are to be applied.
The roadway constructed according to my Invention consists of blocks composed
mainly of concrete or other earthy material, the said blocks being faced with
asphalte or other like material, and having metallic projections, which give sufficient
foot hold for beasts of burden and for other purposes.
Although I prefer to employ asphalte or pitch for facing the blocks, yet I do not
limit myself thereto, as any other substance or composition having similar physical
properties may be employed instead of asphalte or pitch.
In order to facilitate the lifting of roadways composed of my improved blocks I
construct some of the central studs with taper holes, so as to form what is commonly
known as "lewis" holes. By means of these "lewis" holed studs the blocks may

page_text: be connected with suitable tackle for lifting or replacing them without undue
disturbance of the roadway.
Blocks or setts made according to my Invention may be made of such dimensions
as to cover hollow portions of a roadway, thus dispensing with arches.
In cases where it is required to pass pipes, sewers, or telegraph wires along
streets, I construct a subway of concrete or other material, upon the side walls of
which subway I rest blocks made according to my Invention of such dimensions
as to form a cover of sufficient strength to bear with safety any required weight.
In this case I sometimes place iron bars or rods in the mould before it is quite
filled with concrete. These bars or tension rods being embedded in the concrete,
and having their ends bent to prevent longitudinal notion, greatly increase the
strength of the blocks and resist fracture from the weight passing over the covered
way formed by them.
In applying my Invention to the side walks of streets (not used for horso and
wheel traffic), and to other like walks and to flooring, I dispense with the iron
gratings, and after placing the heated broken materials on the melted asphalte
placed in the bottom of the mould, fill up the said mould to the desired height
with concrete, thus forming an artificial flag of the required thickness, which I use
as a substitute for brick or stone paving, the edges of the said flags being joined
together in the ways described with respect to paving blocks or setts.
Having now described the nature of iny Invention, and the manner in which the
same is to be performed, I wish it to be understood that I claim as my Invention
of "Improvements in Roadways, Pavements, and other like Surfaces,-
First. Forming roadways, pavements, and other like surfaces of blocks or setts
composed mainly of concrete or other earthy material, the said blocks or setts being
faced with asphalte or other like material, and having metallic projections, which
give sufficient foot hold for beasts of burden and for other purposes, substantially
as hereinbefore described and illustrated in the accompanying Drawing.
Secondly. Forming roadways, pavements, and other like surfaces of blocks or
flags, composed mainly of concrete or other earthy material faced with asphalte or
other like material, the facing of asphalto or other like material being without
metallic projections, as herein before described.
Thirdly. The method of ensuring the adhesion of the component parts of paving
blocks or setts composed of concrete and bituminous material, either with or without
metallic projections, substantially as herein described.
In witness whereof, I, the said James Herd, have hereunto set my hand
and seal, this Twenty fifth day of November, in the year of our Lord One
thousand eight hundred and eighty one.