IMPROVEMENTS IN THE MANUFACTURE OF PAVING SLABS, BLOCKS, PIPES, EMERY WHEELS, GRINDSTONES, AND OTHER ARTICLES FROM PLASTIC OR SEMI-DRY MATERIALS, AND IN THE MACHINERY OR APPA- RATUS EMPLOYED THEREIN."
Year: 1877

page_text: "
LETTERS PATENT to James Hodges, of Bagshot, in the County of Surrey,
and James William Butler, of Willesden, in the County of Middlesex,
for the Invention of IMPROVEMENTS IN THE MANUFACTURE OF PAVING
SLABS, BLOCKS, PIPES, EMERY WHEELS, GRINDSTONES, AND OTHER ARTICLES
FROM PLASTIC OR SEMI-DRY MATERIALS, AND IN THE MACHINERY OR APPA-
RATUS EMPLOYED THEREIN."
Sealed the 5th March 1878, and dated the 18th September 1877.
PROVISIONAL SPECIFICATION left by the said James Hodges and James
William Butler at the Office of the Commissioners of Patents on the 18th
September 1877.
JAMES HODGES, of Bagshot, in the County of Surrey, and JAMES WILLIAM
BUTLER, of Willesden, in the County of Middlesex. IMPROVEMENTS IN THE
MANUFACTURE OF PAVING SLABS, BLOCKS, PIPES, EMERY WHEELS, GRINDSTONES,
AND OTHER ARTICLES FROM PLASTIC OR SEMI-DRY MATERIALS, AND IN THE
MACHINERY OR APPARATUS EMPLOYED THEREIN."
Our Invention relates to the production of paving slabs, blocks, pipes, emery
wheels, grindstones, and other articles from plastic or semi-dry materials;
and it consists of improvements in the composition of such articles and in the
mode of moulding the same, and also in the machinery or apparatus employed
in performing that operation.
In carrying out our Invention as applied, for example, to the production of
paving slabs, we prepare any suitable cement, such, for example, as Portland
cement, or the improved composition herein-after described, and we introduce
the material or composition so prepared into open moulds placed (previously to
the introduction of the material thereinto) upon a table, which we designate a
trembling" table, that is to say, one to which a vertical shaking or tremulous
motion is imparted. The table, which by preference rests upon and is connected
to a frame so as to be free to move vertically, being alternately lifted from and

page_text: allowed to fall upon its support, so as to produce a tremulous action upon the
mould, whereby the material therein is condensed as it is supplied to the mould
without the necessity for tamping or ramming, or for any other manipulation
than the smoothing of the surface by means of a trowel or similar instrument.
In order to obtain the before-mentioned vertical shaking or tremulous motion
of the table various mechanical devices may be employed, but we prefer to use
cams acting upon the under side of the table, such cams being mounted at
intervals upon horizontal shafts driven through the intervention of gearing
from a driving shaft actuated by any suitable prime mover.
When it is required to produce pipes, emery wheels, grindstones, and other
articles from plastic or semi-dry materials, we proceed in a similar manner, the
cement, composition, or materials employed being varied according to the
nature of the article which it is required to obtain.
In some cases (more particularly in the manufacture of emery wheels and
grindstones) the material as it is supplied to the mould may be subjected to
a slight tamping by the aid of an instrument having pendent projections,
and operated by hand.
Our improved composition, which is specially applicable to pipes, emery wheels,
and grindstones, consists of asbestos, ground or otherwise reduced, mixed or incor-
porated with the materials from which the articles are ordinarily manufactured.
In the production of pipes we mix the asbestos in a fine state of division
with the cement, ground flints, slag, broken granite, and the like, of which
the pipes are composed in the case of concrete pipes, and with clay in the case
of earthenware pipes.
For the production of emery wheels or grindstones we mix the asbestos,
prepared as before mentioned, with magnesian cement and emery or broken
silex, as the case may be.
The use of asbestos has the advantage over other fibrous materials employed
in conjunction with plastic or semi-dry materials, that whereas fibrous materials
generally are liable to deterioration under the influence of moisture, and also
to be consumed under the action of heat (to which in the case of fired ware
the article is subjected in baking or burning), the asbestos is indestructible,
so that the increased cohesive strength which it imparts to the article is
unimpaired by any operation to which the article may be subjected during or
subsequent to its manufacture.
We also prepare a cement to be used in the manufacture of paving slabs,
blocks, pipes, emery wheels, grindstones, and other articles in the following
manner: We take oxide of magnesium, to which we add sulphur in the pro-
portion of, say, from 3 to 5 per cent., and we mix therewith emery, silex, or
other materials, according to the purpose to which the cement is to be applied.
We then mix with these ingredients a sufficient quantity of saturated solution
of sal ammoniac to form, with the addition of chloride of magnesium, a con-
sistency suitable for moulding.
In the case of pipes, emery wheels, or grindstones we may, if desired, incor-
porate with the materials before mentioned asbestos prepared in the manner
herein-before described.
It is obvious that our improved composition is also applicable to the pro-
duction of articles of the description before mentioned by the aid of apparatus
other than that herein-before described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said James Hodges and James William Butler in the Great Seal
Patent Office on the 13th March 1878.
JAMES HODGES, of Bagshot, in the County of Surrey, and JAMES WILLIAM
BUTLER, of Willesden, in the County of Middlesex. · IMPROVEMENTS IN THE
MANUFACTURE OF PAVING SLABS, BLOCKS, PIPES, EMERY WHEELS, GRINDSTONES,
AND OTHER ARTICLES FROM PLASTIC OR SEMI-DRY MATERIALS, AND IN THE
MACHINERY OR APPARATUS EMPLOYED THEREIN."
Our said Invention relates to the production of paving slabs, blocks, pipes,
emery wheels, grindstones, and other articles from plastic or semi-dry materials;
and it consists of improvements in the composition of such articles and in the
mode of moulding the same, and also in the machinery or apparatus employed
in performing that operation.
In carrying out our said Invention we prepare any suitable cement, such, for
example, as Portland cement, or one of the improved compositions herein-after
described, and we introduce the material or composition so prepared into open
moulds placed (previously to the introduction of the material thereinto) upon a
table, which we designate a trembling" table, that is to say, one to which a
vertical shaking or tremulous motion is imparted. The table, which by pre-
ference rests upon and is connected to a frame so as to be free to move vertically,
being alternately lifted from and allowed to fall upon its support, so as to pro-
duce a tremulous action upon the mould, whereby the material therein is
condensed as it is supplied to the mould without the necessity for tamping or
ramming, or for any other manipulation than the smoothing of the surfaco
by means of a trowel or similar instrument.
One part of our improvements in compositions, which is applicable to pipes,
emery wheels, and grindstones, consists in the use of asbestos, ground or other-
wise reduced, mixed or incorporated with the materials from which the articles
are ordinarily manufactured, or which form their main constituents.
Another part of our improvements in compositions consists of a cement to be
used in the manufacture of paving slabs, blocks, pipes, emery wheels, grind-
stones, and other articles, and which is composed of oxide of magnesiumi and
sulphur, together with emery, silex, or other materials, according to the purpose
to which the cement is to be applied, to which ingredients are added a suffi-
cient quantity of saturated solution of sal ammoniac to form, with the addition
of chloride of magnesium, a consistency suitable for moulding.
And in order that our said Invention may be fully understood we shall now
proceed more particularly to describe the same, and for that purpose shall
refer to the several Figures on the annexed Sheet of Drawings, the same letters
of reference indicating corresponding parts in all the Figures.
Figure 1 of the accompanying Drawings represents a longitudinal sectional
elevation of a machine for moulding paving slabs constructed according to our
said Invention Figure 2 is a plan of the same with the table and mould
removed; and Figure 3 is an end elevation corresponding to Figure 1.
Figure 4 represents an instrument which may be used as an auxiliary, as
hereinafter explained.
A is the frame of the machine, which is made of a length and width adapted
to the dimensions of the paving slabs to be produced, and is formed horizontal
on its upper surface a for the reception of the trembling table B, which con-
stitutes an important feature of our said Invention: this table is connected to
the frame A by means of bolts carried by the table and passing through aper-
tures in the frame, so as, whilst retaining the table in position laterally and
endwise, to admit of its alternately rising from and falling upon its support a;
this motion of the table may be obtained in various ways, but the arrangement

page_text: shewn in our Drawings, and next hereinafter described, is the best mode with
which we are acquainted of carrying out the Invention.
C, C, are longitudinal shafts mounted in bearings c, c, in the frame A, and
each carrying a series of cams D, D, for acting upon the under side of the
table; these shafts are driven in the direction indicated by the corresponding
arrows in Figure 3 through the intervention of gearing E, E', E', from a
main shaft F mounted in bearings d, d, and carrying driving pullies G, G, for
receiving motion from any suitable prime mover.
The operation of making paving slabs with the improved apparatus is carried
out in the following manner, videlicet: We provide a number of open moulds
of dimensions corresponding to those of the slabs to be produced, one of which
moulds is placed upon the table B, as shewn at II, and the cement, such, for
example, as Portland cement, or our improved composition, having been prepared,
the apparatus is set in motion, and we introduce the material or composition so
prepared into the mould II. Under the action of the cams D, D, the table B
alternately rises and falls, it being elevated by the portions e, e, of the cams,
and suddenly allowed to fall again on to the support a as soon as, by the
continued rotation of the shafts C. C, the portions c. c, have passed out of the
range of the under side of the table. By these means a tremulous motion is
imparted to the mould H, situate upon the table B, whereby the material is
condensed as it is supplied to the mould without the necessity for tamping
or ramming, or for any other manipulation than the smoothing of the surface
by a trowel or similar instrument.
As soon as the mould is completely full it is removed from the table B and
allowed to stand for a sufficient period for the slab to set and harden, and
its place having been supplied by another similar mould the operation is
repeated, and so on in succession.
When it is required to produce pipes, emery wheels, grindstones, and other
articles from plastic or semi-dry materials, we proceed in a similar manner,
the cement, composition, or materials employed being varied according to the
nature of the article which it is requested to obtain.
In some cases (more particularly in the manufacture of emery wheels and
grindstones) the material as it is supplied to the mould may be subjected to a
light tamping by the aid of an instrument I, Figure 4, having pendant pro-
jections, and operated by hand, the instrument being used Hatwise with
the projections downwards.
Our improved composition, which is applicable to pipes, emery wheels, and
grindstones, consists of asbestos, ground or otherwise reduced, mixed or incor-
porated with the materials from which the articles are ordinarily manufactured,
er which form their main constituent.
In the production of pipes we mix the asbestos in a fine state of division
with the cement, ground flint, slag, broken granite, and the like, of which the
pipes are composed in the case of concrete pipes, and with clay in the case of
earthenware pipes.
For the production of emery wheels or grindstones we mix the asbestos,
prepared as before mentioned, with magnesian cement, to which is added emery
or broken silex, as the case may be.
We prefer to use the asbestos in the proportion of about three per cent. by
weight of the other materials employed, but this proportion will vary accord-
ing to circumstances.
The use of asbestos has the advantage over other fibrous materials employed in
conjunction with plastic or semi-dry material, that whereas fibrous materials
generally are liable to deterioration under the influence of moisture, and also
to be consumed under the action of heat (to which in the case of fired ware
the article is subjected in baking or burning), the asbestos is indestructible,
so that the increased cohesive strength which it imparts to the article is unim-
paired by any operation to which the article may be subjected during or
subsequent to its manufacture.

page_text: We also prepare a cement to be used in the manufacture of paving slabs,
blocks, pipes, emery wheels, grindstones, and other articles in the following
manner: We take oxide of magnesium, to which we add sulphur in the
proportion of, say, from three to five per cent., and we mix therewith emery,
silex, or other materials, according to the purpose to which the cement is to
be applied. We then mix with these ingredients a sufficient quantity of
saturated solution of sal ammoniac to form, with the addition of chloride of
magnesium, a consistency suitable for moulding.
In the case of pipes, emery wheels, or grindstones we may, if desired, incor-
porate with the materials before mentioned asbestos prepared in the manner
herein-before described.
It is obvious that our improved compositions are also applicable to the pro-
duction of articles of the description before mentioned by the aid of apparatus
other than that herein-before described.
Having now described and particularly ascertained the nature of our said
Invention, and the manner in which the same is or may be used or carried
into effect, we would observe in conclusion that what we consider to be novel
and original, and therefore claim as the Invention secured to us by the herein-
before in part recited Letters Patent is,―
First. The system or mode of moulding paving slabs, blocks, pipes, emery
wheels, grindstones, and other like articles composed of plastic or semi-dry
materials, by imparting a shaking or tremulous motion to the mould as the
material is introduced, substantially as herein-before described.
Secondly. A moulding machine consisting of a table operated so as to be
alternately elevated and allowed to fall, substantially as and for the purposes
herein before described.
Thirdly. The application and use to and in the manufacture of pipes, emery
wheels, and grindstones of asbestos in a fine state of division mixed or incor-
porated with the other materials which form the main constituents of the
said articles, substantially as herein-before described.
Fourth. The peculiar cement for paving slabs, blocks, pipes, emery wheels,
grindstones, and other articles, prepared substantially in the manner herein-
before described.
In witness whereof, I, the said James William Butler, on behalf of myself
and the said James Hodges, have to this our Specification set my hand
and seal, the Seventh day of March, One thousand eight hundred and
cavonty-night
JAMES WILLIAM BUTLER. (L.S.)