IMPROVEMENTS IN THE COMBINATION OF REFUSE MATERIALS OF GLASS WORKS WITH OTHER SUBSTANCES FOR THE PURPOSE OF MAKING FLAGS FLATTENING STONES BRICKS TILES AND OTHER LIKE FICTILE OR VITREOUS ARTICLES WHICH IMPROVEMENTS ARE ALSO APPLICABLE IN THE CASE OF SIMILAR MATERIALS FROM OTHER SOURCES THAN GLASS WORKS
Year: 1883

page_text: LETTERS PATENT to William Douglas Herman of St Helens in the County
of Lancaster, for an Invention of "IMPROVEMENTS IN THE COMBINATION OF
REFUSE MATERIALS OF GLASS WORKS WITH OTHER SUBSTANCES FOR THE
PURPOSE OF MAKING FLAGS FLATTENING STONES BRICKS TILES AND OTHER
LIKE FICTILE OR VITREOUS ARTICLES WHICH IMPROVEMENTS ARE ALSO
APPLICABLE IN THE CASE OF SIMILAR MATERIALS FROM OTHER SOURCES
THAN GLASS WORKS,"
PROVISIONAL SPECIFICATION left by the said William Douglas Herman at
the Office of the Commissioners of Patents on the 23rd January 1883.
WILLIAM DOUGLAS HERMAN of St. Helens in the County of Lancaster
"IMPROVEMENTS IN THE COMBINATION OF REFUSE MATERIALS OF GLASS WOrks
WITH OTHER SUBSTANCES, FOR THE PURPOSE OF MAKING FLAGS, FLATTENING STONES,
BRICKS, TILES, AND OTHER LIKE FICTILE OR VITREOUS ARTICLES, WHICH IMPROVE-
MENTS ARE ALSO APPLICABLE IN THE CASE OF SIMILAR MATERIALS FROM OTHER
SOURCES THAN GLASSWORKS
"
This invention consists mainly in combining the refuse silicious materials, thrown
out so abundantly from glass works, but also found elsewhere with or without
other admixture with an alkaline silicate (preferably silicate of soda) as a binding
material by means of heat.
The waste materials I especially refer to, are 1st the fine sand after being used
for grinding, of which several thousands of tons a week are at present thrown
away. 2d the used silica brick, also thrown away in great quantity, and like the
sand, composed, with the exception of two or three per cent, exclusively of silica.
Also the flattening stones, which after a time disintegrate or form rough surfaces,
and have to be thrown away, these also are very largely composed of silica-and
for the purposes of my invention require, like the silica bricks, to be brought first
into a state of granulation.

page_text: To form bricks, tiles, flags, flattening stones, and other like articles, I mould the
sand, or mixed sand and granulated silica brick or granulated or powdered flatten-
ing stones, with a solution of soluble glass (silicate of soda or potash) in sufficient
quantity to cause them to adhere, the exact amount varying with the different
substances and uses. The mixture is well mixed, kneaded, moulded, pressed, dried,
and baked.
Sometimes to give greater power of resisting heat, coarse sand, or silica in other
forms, such as old silica bricks ground to different degrees of fineness, may be added
to the mixture, also potsherds or other fire-resisting material. To impart porosity
and lightness, carbonaceous material, such as charcoal, sawdust, coke or cinders inay
be incorporated with the mixture. Ground soapstone or steatite imparts its peculiar
smoothness, which is very valuable in certain cases. When the bricks or artificial
stone are required to withstand sudden changes of temperature it is desirable to
incorporate some asbestos, the fibrous nature of which prevents cracking. I also
sometimes add ground copper-works slags, or the refuse waste of soda ash manu-
factures, especially that made in the Pechiney or Pechiney-Weldon modification of
the Leblanc process, together with some alkali to the above-mentioned materials,
when an excellent material results for fictile or vitreous manufactures not requiring
great clearness or transparency; several rich shades of blue, green, brown, and
black being obtainable by this means.
As soluble glass made in the ordinary manner is costly, for the purposes of my
invention where colour is no object, a cheap material made by furnacing a mixture
of the refuse sand with carbon fuel and one of the sulphates, even Chlorides of the
Alkalies, will do.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Douglas Herman in the Great Seal Patent Office on the
23rd July 1883.
WILLIAM DOUGLAS HERMAN of St Helen's, in the County of Lancaster
"IMPROVEMENTS IN THE COMBINATION OF REFUSE MATERIALS OF GLASS-WORKS
WITH OTHER SUBSTANCES FOR THE PURPOSE OF MAKING FLAGS, FLATTENING STONES,
BRICKS, TILES, AND OTHER LIKE FICTILE OR VITREOUS ARTICLES, WHICH IMPROVE-
MENTS ARE ALSO APPLICABLE IN THE CASE OF SIMILAR MATERIALS FROM OTHER
SOURCES THAN GLASS WORKS
"
This invention consists mainly in combining the refuse silicious materials, thrown
out so abundantly from glass works, but also found elsewhere, with or without
other admixture, with an alkaline silicate, (preferably silicate of soda) as a binding
material, by means of heat.
The waste materials I especially refer to are 1st the fine sand after being used
for grinding, of which several thousand of tons a week are at present thrown away
2nd the used silica brick, also thrown away in great quantity, and like the sand,
composed, with the exception of two or three per cent, exclusively of silica-Also
the flattening stones which after a time disintegrate or form rough surfaces, and
have to be thrown away-these also are very largely composed of silica-and for
the purposes of my invention require, like the silica bricks, to be brought first into
a state of granulation.
To form bricks, tiles, flags, flattening stones and other like articles, I mould the
sand or mixed sand and granulated silica brick, or granulated or powdered flatten-
ing stones, with a solution of soluble glass (silicate of soda or potash) in just
sufficient quantity to cause them to cohere well, the exact amount and strength
varying with the different substances and uses. A large proportion of silicate
gives a harder product, and when this result is desired it may be obtained either
by using a large quantity of weak solution, or a smaller quantity of strong solu-
tion. In the case of materials in a very fine state of division, such as the sand
which has been used for grinding plate glass, I prefer, if the said materials are dry,
to use a large quantity of weak solution, but if used in the wet state allowance
must be made for the water present, and a stronger solution employed. In the
case of very coarsely granulated materials, such as old silica bricks, a large quantity
of solution cannot be absorbed, and a stronger solution should be used. It must
be borne in mind that the soluble silicates act as a flux, and when it is desired that
the finished articles should have great power to resist heat, the proportion of
silicate used should be limited to the smallest quantity capable of giving the
required coherence. The mixture is well mixed, kneaded, moulded, and pressed
either by hand or by suitable machinery, dried and baked in an ordinary brick or
tile kiln to a bright red heat, or (in the case for instance of fire-resisting silica
bricks) to a white heat
Sometimes to give greater power of resisting heat, coarse sand, or silica in other
forms, such as old silica bricks ground to different degrees of fineness, may be added
to the mixture, also potsherds or other fire resisting material. To impart porosity
and lightness, carbonaceous material, such as charcoal, sawdust, coke, or cinders
may be incorporated with the mixture. Ground soapstone or steatite imparts its
When the bricks or
peculiar smoothness, which is very valuable in certain cases.
artificial stone are required to withstand sudden changes of temperature, it is
desirable to incorporate some asbestas, the fibrous nature of which prevents

page_text: cracking. In this way with or without asbestos, old silica brick is worked up
into new bricks or blocks, old flattening stones into new flattening stones and
refuse grinding silica into good building brick and medium, or good silica fire-
brick. When mixed with the smallest quantity of soluble silicate required to
make it cohere, and gently fired, the refuse grinding sand forms a material very
similar in texture to " Bath brick," and equally useful for cleaning and brightening
.metals etcetera. When mixed with a larger quantity of soluble silicate, and fired
so as to produce a hard product, a material is formed well adapted for fine grind-
stones and whetstones, to which greater. "bite" may be imparted by the addition
of some coarse sand, sandstone, or emery of a suitable degree of granulation.
The following quantities of materials are good examples. For medium quality
silica fire-bricks, building bricks, flags etcetera and fine grindstones, 100 parts of
the fine refuse sand, which has been used for grinding plate glass, mixed with 25
to 30 parts of solution of silicate of soda, of about 112 specific gravity. This
quantity of solution is calculated for use with dry refuse sand, but as it is usually
more or less damp, allowance must be made for the water contained in it, and such
quantity of stronger solution added, as will give about the above named proportion
of silicate. Thus for instance with sand containing say 15 per cent of water it
would be necessary to add only 15 parts of silicate, of soda solution of 1.24 specific
gravity to 115 parts of the wet sand instead of 30 parts of solution of 1.12 specific
gravity to 100 parts of dry sand. For "Bath bricks" 100 parts refuse sand con-
taining 15 per cent of water, mixed with 10 parts of silicate of soda solution of
about 1.05 specific gravity. The bricks it is hardly necessary to mention may be
made harder or softer as desired by increasg or diminishing the proportion of
soluble silicate. For a better quality of silica fire brick it is desirable to incorporate
with the fine waste sand a more refractory form of silica, such as coarsely ground
Dinas bricks or coarse grained sand-A good mixture is 50 parts of waste sand,
50 parts of old Dinas bricks, ground so as to pass through a riddle with half inch
apertures, and 15 to 20 parts of silicate of soda solution (calculated on the dry
solid materials) of 11 to 13 specific gravity-It is obvious that the size of the
particles of old Dinas bricks, as well as the proportion relative to the waste sand,
may be varied considerably. A large proportion gives a more refractory brick but
less easy to mould, and increase in the size of the fraginents has, though to a
slighter extent, the same effect.
A good, hard silica brick which moulds well, may be made by mixing 50 paris
of fine refuse sand with 50 parts of coarse sand, and 15 parts of silicate of soda
solution (calculated on the dry solid materials) of 12 to 1.35 specific gravity.
A good silica brick, also adapted for building purposes, for flags, grindstones
etcetera may be made by mixing 100 parts of "burgy" (the coarser portion of the
refuse sand) with 15 to 20 per cent of silicate of soda solution, calculated on dry
'burgy" of 1.25 to 1.35 specific gravity.
"
A very light porous silica brick, well adapted for situations where a low gravity
is desirable, also suitable as a filtering medium, may be made by mixing ground
charcoal or other carbonaceous material with waste sand or 'burgy," and silicate
of soda, and firing whereby the organic matter is destroyed and the product
rendered very porous; 80 to 95 parts of "burgy" with 20 to 5 parts of ground
charcoal, mixed with 18 to 25 parts of silicate of soda solution (calculated on the
dry solid materials) of 1.2 to 135 specific gravity are good mixtures, but it is
obvious that the proportion of charcoal as well as the size of the particles, which
governs the size of the pores in the finished product, may be varied considerably.
A highly refractory silica brick may be made by mixing coarsely ground Dinas,
or other old silica bricks of good quality, with a small proportion of silicate of soda
solution Very coarse particles give a highly refractory but somewhat tender
brick. I prefer to grind the old bricks so that about one half will pass through a
sieve with 10 to 16 meshes to the lineal inch, and the other half rejected by these
sieves, should preferably nearly all pass through a riddle with half inch apertures.
A good mixture is 100 parts of old ground brick with 20 to 30 parts of silicate of

page_text: soda solution of 1·1 to 1.2 specific gravity. These bricks should be fired at a good.
white heat.
A mixture giving a very fine smooth surface well adapted for flattening stones,
is the following-50 parts of old flattening stone, or the small waste pieces from
the quarry, ground so as to pass through a sieve with 56 meshes to the lineal inch,
50 parts of very finely ground steatite which will pass through a sieve with
100 meshes to lineal inch (that is 10,000 meshes: to the square inch) and 25 to
30 parts of solution of silicate of soda of about 1.3 specific gravity-When the
stone is required to stand sudden changes of temperature the mixture may be
improved by the addition of 2 to 10 per cent of asbestos In the process of
moulding and pressing these flattening stones a larger proportion of silicate solution
is concentrated at the exterior surfaces, forming when the stone is fired, a close
hard skin. The hardness of this skin may be increased by immersing the stone,
either before or after burning, in a solution of soluble silicate, drying and firing,
and in a similar manner, when one skin has been worn through a fresh one may
be formed-A mixture suitable for flattening stones that are not subjected to
rapid changes of temperature, and for moulds for shaping heated glass, consists of
100 parts of dry "burgy" and 20 to 25 parts of silicate of soda solution of about
1-32 specific gravity. This gives a close hard stone capable of being dressed with
chisel, and ground to a very fine surface--The great advantage of flattening stones,
made according to my invention, is that being prepared from carefully ground and
sifted materials they are absolutely free from the pebbles always found even in the
very best natural flattening stones, and which are a source of great injury to the
glass flattened upon them, by rendering the surface uneven. By reason of the
smooth surface and uniform hardness of the "skin" above described and of the
stones made from "burgy" or similar material, glass may be flattened upon them
without the intervention of a "largre," thereby effecting a considerable economy.
All the mixtures given above when properly fired are almost absolutely
insoluble. I also make glass of various colors of the waste silicious material
resulting from the grinding of plate glass, for which it is well adapted by its fine
state of division and ready fusibility. When mixed with the ingredients
commonly employed in the window glass manufacture, it produces a glass with a
green tint, but other colors may be obtained by the addition of well known
coloring materials. In addition to the substances commonly employed in glass
making, and using this waste silica in place of sand, I have obtained fine bluish
green tints with the slag from copper works, and rich shades of green, brown and
black with the refuse from the soda ash manufacture by the Leblanc process,
commonly called "alkali waste." The variety of this substance which I prefer is
that made by the Pechiney, or Pechiney-Weldon modification of the Lellanc
process. When Alkali waste is used in conjunction with sulphate of soda it is
usually unnecessary to add carbon to facilitate the decomposition of the latter, as
the alkali waste itself contains sufficient carbon for this purpose. The exact
quantities of copper slag or of alkali waste vary with the quality and appearance
of the glass required-in the case of copper slag the quantity may vary till the
slag is from three to fifteen per cent of the entire materials employed, and in the
case of alkali waste from five to twenty-five per cent of the entire mixture, are
about the most satisfactory limits For many of the purposes mentioned in this
specification and for others where color is of no great importance, soluble glass or
silicates of the Alkalies may be very cheaply manufactured by using refuse sand
from glass works, in combination with a cheaper source of alkali than the
carbonates usually employed, such as the sulphates or even chlorides, but I prefer
sulphate of soda. When sulphate is employed, slack should be added to facilitate
its decomposition. Good proportions are as follows-405 per cent of dry waste
sand, 41.5 per cent of salt cake, and 18 per cent of slack. A batch of any con-
venient weight, mixed in the above proportions, is fluxed in a reverberatory
furnace, and the product dissolved in hot water to the required strength.
Having now described my invention and the best mode known to me of

page_text: carrying it into effect, I claim as my Invention to be secured to me under the
letters patent.
1 The manufacture of flags, flattening stones, bricks, tiles, and other like fictile
ware from waste silicious materials with or without asbestos, emery, steatite,
coloring matter or the like, by the aid of soluble glass, substantially as described.
2nd The manufacture of vitreous articles by the addition of copper slag, or
alkali makers waste, to ordinary glass making materials, in which waste silicious
materials are used for silica, substantially as described.
3rd The application of silicate of soda, made from waste silicious material and
sulphate of soda, or other like salt, as described, as a cheap binding material in the
manufacture of bricks, and other articles from waste silicious materials, with or
without other admixture, substantially as described.
In witness whereof I the said William Douglas Herman have hereunto set my
hand and seal this twentieth day of July in the year of our Lord one thousand
eight hundred and eighty three
W. DOUGLAS HERMAN
(L.S.)