IMPROVEMENTS IN THE MANUFACTURE OF HOLLOW BRICKS OR BLOCKS TO BE USED FOR THE FLOOR, CEILINGS, AND OTHER PARTS OF BUILDINGS, AND IN APPARATUS FOR MOULDING OR MANUFACTURING THE SAME
Year: 1868

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn
Fields, in the County of Middlesex, Gentleman, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF HOLLOW BRICKS OR BLOCKS TO
BE USED FOR THE FLOOR, CEILINGS, AND OTHER PARTS OF BUILDINGS, AND IN
APPARATUS FOR MOULDING OR MANUFACTURING THE SAME."-A communi-
cation from abroad by Francois Louis Sabrout, of Paris, in the
Empire of France.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition,
on the 15th May 1868.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County
5 of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE MANUFACTURE OF HOLLOW BRICKS OR
BLOCKS TO BE USED FOR THE FLOORS, CEILINGS, AND OTHER PARTS OF BUILDINGS,
AND IN APPARATUS FOR MOULDING OR MANUFACTURING THE SAME,"

page_text: munication to me from abroad by Francois Louis Sabrout, of Paris, in
the Empire of France, to be as follows:-
This Invention relates to an improved manufacture of closed hollow
pannelled bricks or blocks to be used in substitution for ordinary lath
and plastering for the floors, ceilings, and other parts of buildings
whereby economy, lightness, strength, and diminution or deadening of
sound are obtained.
According to one part of this Invention it is proposed, after the
hollow blocks have been moulded by pouring plaster or other suitable
material in a semi-fluid state into suitable moulds containing cores, to
close up the open mouths of the cavities left by the subsequent with-
drawal of the cores by the aid of a second mould composed of caoutchouc
or other elastic or flexible material in contradistinction to wood or
rigid materials... Suitable projections are made inside this mould in order
that when the plaster is poured therein round the open mouths, such
mouths will be entirely closed with the exception of a few small perfora-
tions which facilitate the drying of the block by admitting air therein,
whilst they also form a key or hold for the plaster or cement to penetrate
when setting the blocks, and thus key or hold them firmly together.
The use of india-rubber moulds for the purpose referred to admits of
'the free expansion in the blocks.
Another mode of making closed hollow blocks consists in the em-
ployment of hollow cores composed of plaster or other light and cheap
material, which cores having been adjusted in the mould and the
plaster or other material employed in casting or moulding the
hollow blocks having been poured into or otherwise introduced into
the mould, are allowed to remain therein in lieu of being withdrawn
and leaving open cavities on one side of the block which require to
be closed as above described by the aid of a second mould, whereas
according to this improved mode of manufacture wherein the cores
are allowed to remain in, the operation of closing is entirely dispensed
with. These cores may be composed of coarse canvass or like material
wrapped round a suitable mandril and coated or covered with plaster.
When set or dry they are taken off the mandril and placed in the
mould, where they remain.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 14th November 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Mid-
dlesex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of May, in the year of our
Lord One thousand eight hundred and sixty-eight, in the thirty-first
year of Her reign, did for Herself, Her heirs and successors, give and
grant unto me, the said John Henry Johnson, Her special license that
I, the said John Henry Johnson, my exccutors, administrators, and
assigns, or such others, as I, the said John Henry Johnson, my
executors, administrators, or 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 MANUFACTURE OF HOLLOW BRICKS OR BLCCKS TO BE USED FOR THE FLOORS,
CELLINGS, AND OTHER PARTS OF BUILDINGS, AND IN APPARATUS FOR MOULDING
OR MANUFACTURING THE SAME," a communication from abroad by Francois
Louis Sabrout, of Paris, in the Empire of France, upon the condition
(amongst others) that I, the said John Henry Johnson, my executors'
or administrators, by an instrument in writing under my hand and seal,
should particularly describe and ascertain the nature of the said Inven-
tion, 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 John Henry Johnson, 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, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to
say:-

page_text: The said Invention relates to an improved manufacture of closed
hollow panels, bricks, or blocks to be used in substitution for ordinary
lath and plastering for the floors, ceilings, and other parts of buildings.
Panelled bricks composed of plaster and other substances substituted
for the lathwork of ceilings and floors, and for the construction of
slight partitions have hitherto been made in moulds containing cores
intended to produce the hollows or cavities, such cores being subsc-
quently withdrawn through one of the faces of the panel which remains
open and which is subsequently closed by plaining the panel vertically
in a second mould.
Now this Invention consists of certain improvements in this system
of manufacturing hollow panelled bricks, which improvements are
herein-after described and illustrated by the accompanying Sheet of
Drawings.
Figure 1 of the Drawings is a longitudinal vertical section of the
mould employed for closing the panelled bricks taken along the
line I, J, (Figure 3); Figure 2 a transverse vertical section of the same
taken along the line K, L, and Figure 3 is a plan of the said mould;
Figure 4 is a longitudinal section of the improved mould for the
manufacture of panelled bricks taken along the line A, B, (Figure 5);
Figure 5 a part plan and part horizontal section thereof taken along
the line E, F, (Figure 4); Figure 6 is a transverse section taken along
the line C, D (Figure 5); Figure 7 is a transverse section taken
along the line G, H, (Figure 5) shewing the panel or hollow brick
during its manufacture; Figure 8 is a transverse section; Figure 9 a
longitudinal section, and Figure 10 an end view of the core which
is used in the manufacture of the hollow blocks or panelled bricks.
a is the mould for the manufacture of the panelled bricks; b are
projections intended to form holes in the lateral face of the brick in the
process of manufacture; c, moulds composed of wood or metal and
formed of several parts united together into which the plaster or other
material intended to form the hollow bricks is run; d is a core composed
of plaster or of other light and cheap material which is left in the
interior of the bricks; e arc wood or metal rods supporting the cores d;
ff are the hollow panelled bricks in the process of manufacture;
and g and g are handles provided to facilitate the handling of the moulds.

page_text: The first improvement consists in substituting for the wooden mould
used for closing the hollow bricks a single piece a composed of a flexible
and elastic material, such as caoutchouc, as shown in Figs. 1, 2, and 3.
This picce, the internal form of which is identical with the external form
of the sides of the brick, carries three projections b, which penetrate
into the interior of the plaster or other material used, and form openings
or air holes to facilitate the drying and the removal of the piece from
the mould. Into these holes also the plaster or other substance used
for forming the joint penetrates, thus firmly uniting all the pieces com-
posing the flooring so constructed, by which its strength is greatly
augmented. It will be understood that the use of a flexible substance
such as caoutchouc offers greater facility in the manufacture of hollow
panelled bricks than wooden moulds, for the reason that the substances
employed for this purpose are capable when setting of increasing their
volume without inconvenience, since the mould itself yields under the
internal pressure. It is sufficient when running the plastic material
into the mould a to maintain the latter between wooden cross pieces
disposed for that
purpose.
The second improvement in this manufacture, and which is illustrated
by Figures 4, 5, 6, 7, 8, 9, and 10, has for its object the dispensing with
the second operation in the ordinary process of manufacture, viz., the
closing of the hollow brick or panel after it has been run into the
mould. It consists in disposing in the mould ca series of cores d of a
slightly conical form, and light but sufficiently strong, and which cores
after the operation remain imbedded in the substance of which the
hollow panel block or brick is made. These cores & should thereforc
be made of a light and inexpensive material, and plaster or the same
substance of which the hollow panel is composed is by preference
employed. In order to make these cores a coarse cloth such as canvass is
laid round a smooth wooden or metal mandrel previously greased or
soaped, and on this cloth is spread either with a brush or with the hand
a layer of plaster about one-sixteenth to one-eighth of an inch in
thickness. By this means a core is obtained closed on five sides, and
it is simply requisite to close the side left open for the withdrawal of
the mandrel by a cover of wood or plaster previously prepared and
fixed to the core by a layer of the same substance as is used to form
the core, with or without the use of a piece of cloth to increase the

page_text: strength of the whole. The core thus manufactured and which is
shewn in Figures 8, 9, and 10, is provided with apertures at both ends
intended to receive the wooden or metal rods e which pass through the
sides of the detachable mould c, and maintain it firmly in the position
it is required to occupy.. The cores are disposed in a parallel manner
in the mould, as shown in Figure 5, but they may also be arranged so
that the larger end of one core may correspond to the narrow end
of the next; the spaces between the corcs will then be of the same
dimensions and the strength of the hollow panels equal and uniform.
In order to remove the panel from the mould, the rods e which
maintain the cores in their place are withdrawn and the sides of the
mould c removed. The moulds is for this purpose so constructed as
to render it capable of being taken to picces and put together again
with great facility, and is provided with handles which admit of the
two longitudinal faces of the mould being simultaneously either brought
into closer proximity or separated, and when so separated the hollow
moulded panel will leave the mould without difficulty. It will be
understood that the rods e when withdrawn leave apertures which form
air holes, and which when the panels are united admit of the entrance
of the plaster or other material used in forming the joint which renders
the junction firm and strong when these hollow panels are employed
for flooring or partitions. Any light or inexpensive material may be
employed in the manufacture of the cores, such as pasteboard for
example, the main feature of the improvement consisting in leaving
in the interior of the hollow panelled brick in the process of manufac-
ture light and cheap hollow cores by which the operation of closing
the pancl, which in the ordinary way is closed only on five sides, after
it has been run in the moulds provided with mandrels is dispensed with.
Having now described and particularly ascertained the nature of
the said Invention, and the manner in which the same is or may be
used or carried into effect, I would observe in conclusion that what I
consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent is,-
First. The application and use to and in the manufacture of hollow
closed panels bricks or blocks of clastic moulds of caoutchouc or other
suitable material substantially in the manner and for the purpose herein-
before described.

page_text: Second. The application and use to and in the manufacture of hollow
closed panels, bricks, or blocks of hollow cores constructed as herein-
before described and left inside the said panel, brick, or block for the
purpose herein specified.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, the Thirteenth day of
November, One thousand eight hundred and sixty-eight.
J. HENRY JOHNSON. (L.S.)