IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL STONE FOR PAVEMENTS, ROADWAYS, SUBMARINE WALLS, SEWERS, PIPES, AND OTHER SIMILAR CONSTRUCTIONS
Year: 1871

page_text: LETTERS PATENT to Robert Skinner, of the City and County of San
Francisco, State of California, United States of America, for the
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL STONE
FOR PAVEMENTS, ROADWAYS, SUBMARINE WALLS, SEWERS, PIPES, AND OTHER
SIMILAR CONSTRUCTIONS."
Sealed the 15th September 1871, and dated the 8th July 1871.
PROVISIONAL SPECIFICATION left by the said Robert Skinner at
the Office of the Commissioners of Patents, with his Petition, on
the 8th July 1871.
I, ROBERT SKINNER, of the City and County of San Francisco, State
5 of California, United States of America, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL
STONE FOR PAVEMENTS, ROADWAYS, SUBMARINE WALLS, SEWERS, PIPES, AND OTHER
SIMILAR CONSTRUCTIONS," to be as follows:-
The first part of my Invention relates principally to a new com-
bination of materials to form a concrete block of the desired shape
to construct a wall, roadway, or pavement; and consists mainly in the

page_text: employment of earthy, bituminous, & pitchy substances combined with
calcareous rock, the whole being subjected to a calcining or granulating
process by heat, after which the material is formed into blocks by being
placed in moulds or dies and subjected to a high degree of pressure,
whereby the blocks become a solid and compact mass of great toughness
and enduration.
The second part of my Invention relates to the manner of forming
the said blocks and laying and cementing them where cementing
becomes necessary to form the bond or pavement.
In order to prepare the material in a suitable manner to construct
the blocks, in an oven I place 800 pounds of asphaltum and submit it
to a sufficient degree of heat to expel all of the water and throw off
the gases.
After having been subject to a certain degree of heat, the
intensity and duration of which will be readily understood by workers
of asphaltum, the product becomes calcined and is easily reduced to a
powder; in this state I place the calcined asphaltum in a revolving
cylinder of suitable capacity that can be heated two hundred degrees
(200) Fahrenheit. I now add about (300) three hundred pounds of
pulverized coal slag, three hundred (300) pounds of pulverized coke,
three hundred (300) pounds of limestone or calcareous rock, which is
also granulated or pulverized, and about twenty (20) gallons of mineral
tar.
The tar should be previously boiled in order to expel the water
contained in it, and thoroughly incorporated with the reduced calcareous
or limestone rock, while the said rock is in a heated state and before
adding to the above-named ingredients. It is also essential to form a
perfect combination of the materials that the moisture be expelled from
the coal slag, coke, and calcareous rock before its incorporation with
the granulated asphaltum in the revolving cylinder. The cylinder
should be placed in an inclined position and provided with horizontal
rods or other appliances for thoroughly incorporating and mixing the
whole mass.
During the process of mixing the cylinder is heated so that the
temperature of the mass will be raised to about two hundred degrees
(200°) Fahrenheit, but care should be taken not to employ so great
a degree of heat as to calcine the calcareous component and form quick-
lime.
In some instances the pulverized coal slag and coke may be dispensed

page_text: tionately lessened. After the operation of mixing and heating the
material has been accomplished the product is conducted from the
cylinder to a revolving pan and the temperature lowered to about 150°
Fahrenheit, in which state it is placed in dies or moulds and subjected
to heavy pressure by hydraulic power or otherwise, when a block is
formed of great hardness and durability of the desired shape to construct
the pavement or submarine wall.
In constructing pavements the blocks are bevelled at their top edges
and fluted at the sides. After a section of the blocks have been laid
down in position I cement them together by pouring in the heated
material prepared as above described, but somewhat reduced in strength
by adding a greater proportion of the pulverized or granulated calcareous
rock, so that the filling in the groove and interstices between the blocks
will wear away a little faster than the blocks themselves than by being
of less enduration or hardness and form a foothold for animals passing
over the pavement.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Robert Skinner in the Great Seal Patent Office
on the 6th January 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
SKINNER, of the City and County of San Francisco, State of California,
United States of America, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighth day of July, 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 successors, give
and grant unto me, the said Robert Skinner, Her special licence that
I, the said Robert Skinner, my executors, administrators, and assigns,
or such others as I, the said Robert Skinner, my exccutors, 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 IMPROVEMENTS IN THE MANU-
FACTURE OF ARTIFICIAL STONE FOR PAVEMENTS, ROADWAYS, SUBMARINE WALLS,
68

page_text: SEWERS, PIPES, AND OTHER SIMILAR CONSTRUCTIONS," upon the condition.
(amongst others) that I, the said Robert Skinner, 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 immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said Robert Skinner, 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, reference being had to the accompanying Drawing
forming a part of this Specification :—
The first part of my Invention relates principally to a new combination
of materials to form a concrete block of the desired shape to construct a
wall, roadway, or pavement, and consists mainly in the employment of
earthy, bituminous, and pitchy substances combined with calcareous
rock, the whole being subjected to calcining or granulating by heat,
after which the material is formed into blocks by being placed in
moulds or dies, and subjected to a high degree of pressure, whereby
the blocks become a solid and compact mass of great toughness and
induration.
The second part of my Invention relates to the manner of forming the
said blocks and laying and cementing them where cementing becomes
necessary to form the bond or pavement.
In order to prepare the material in a suitable manner to construct the
blocks, I place in an oven 800 pounds of asphaltum and submit it to a
sufficient degree of heat to expel all of the water and throw off the
gases. After having been subjected to a certain degree of heat, the
intensity and duration of which will be readily understood by workers of
asphaltum, the product becomes calcined and is easily reduced to a
powder; in this state or after having been ground the calcined asphal-
tum is placed in a revolving cylinder of suitable capacity that can be
heated to two hundred degrees (200°) Fahrenheit. I now add about
(300) three hundred pounds of pulverized coal slag, three hundred (300)
pounds of pulverized coke, three hundred (300) pounds of limestone
or calcarcous rock, which is also granulated or pulverized, and about
twenty (20) gallons of mineral tar. The tar should be previously boiled

page_text: ་
in order to expel the water contained in it, and thoroughly incorporate it
with the reduced calcareous or limestone rock while the said rock is in
a heated state and before adding to the above-named ingredients.
It is also essential to the formation of a perfect combination of the
materials that the moisture shall be expelled from the coal, slag,
coke, and calcareous rock before its incorporation with the granulated
asphaltum in the revolving cylinder. The said cylinder should be
placed in an inclined position, and provided with horizontal rods or
other appliances for thoroughly incorporating and mixing the whole
mass.
During the process of mixing, the cylinder is heated so that the
temperature of the mass will be raised to about two hundred degrees
(200°) Fahrenheit, but care should be taken not to employ so great a
degree of heat as to calcine the calcareous component and form quick-
lime, in which case, when combined and formed into a block, it would
have a tendency to slacken upon exposure to atmospheric influences, and
check or crack and crumble the block.
In some instances the pulverized coal slag and coke may be
dispensed with, the quantity of mineral tar to be incorporated being
proportionately lessened. After the operation of mixing and heating
the material has been accomplished the product is conducted from the
cylinder to a revolving pan, and the temperature lowered to about
150° Fahrenheit, in which state it is placed in dics or moulds and
subjected to heavy pressure by hydraulic power, or otherwise; a block
is thus formed of great hardness and durability of the desired shape to
construct the pavement or submarine wall.
Figure 1 represents a bottom view of a block constructed according to
my Invention; Figure 2 is a side view, and Figure 3 an end view of the
same; Figure 4 represents a block for submarine work.
In constructing pavements the blocks A. are bevelled at their top
edges and fluted at the sides; their dimensions are about six inches at
the base and four inches at the top, so that when laid with the broad
surface upon the foundation or bed the edges will touch each other and
form by means of the lesser width at the top a V shaped groove with
numerous vertical holes B beneath extending to the foundation or bed of

page_text: the roadway from curb to curb of the street.
66
The said blocks are laid to
break joint," and their upper edges and corners are all slightly rounded
off, so that no sharp angles will appear on the line of travel.
I prefer to lay my pavement upon a natural foundation or bed of
sand or earth after the road bed has been made as solid and compact
as possible by rolling, pounding, or otherwise. After a section of the
blocks has been laid in position I cement them together by pouring in
the heated material prepared as above described, but somewhat reduced
in strength by the addition of a greater proportion of the pulverized
or granulated calcarcous rock, so that the filling in the grooves and
interstices between the blocks will wear away a little faster than the
blocks themselves and form a foothold for animals passing over the
pavement. The vertical holes also form receptacles for the cement, by
which a more perfect bond of the pavement is had.
In forming blocks C square or oblong for use in building submarine
walls I prepare my dies or moulds so that a hole D shall be left through
the block at each end, through which the guide rods pass in lowering
the block to its bed.
For making pipes, sewers, and tiles the same general formula as
above described may be employed to a certain extent to produce a 1
material of a greater or less degree of toughness and induration by
increasing or reducing the proportion of pulverized or granulated
calcareous rock. By this union of materials and manner of preparation
a combination is formed of substances which have a chemical affinity for
cach other, which when placed under pressure form a solid indurated
block or mass of great toughness, and will be impervious to the action of
the weather or the sun's rays, and not liable to wear away too rapidly
when laid as a pavement or side walk. And when cemented an indis-
soluble bond is formed of the blocks only to be broken for repairs, or
when the foundation is undermined, when the union can again be
formed by cementing.
It is fully believed that the cost will be less than wood for a pavement
and of stone for a sea wall, while a pavement constructed with my
blocks and materials will last much longer than wood, and will not be
liable to shrink or swell from atmospheric influence.
Having thus fully described my said Invention, and the manner in
which the same is to be performed, I claim,-
-

page_text: First. Constructing pavements, roadways, submarine walls, sewers,
pipes, tiles, and the like of the substance herein described with or
without coal slag and coke, as set forth.
Second. The use of calcarcous rock as a component for tempering the
strength and induration of the said ingredients or product when mixed
and compounded in or about in the proportion and manner herein set
forth.
Third. Subjecting the said substances to the necessary degree of heat
and pressure to form a chemical and mechanical union, and effect
the necessary induration of the product, substantially in the manner
described.
Fourth. The construction and employment of the blocks A, or C, with
or without fluted sides or vertical holes B, D, when composed of the
materials herein described and placed under pressure; also cementing
the said blocks with the same material in a liquid state to form a bond
or union in constructing pavements, in the manner substantially as
described.