CERTAIN IMPROVE- HENTS IN MAKING BRICKS AND TILES
Year: 1808

page_text: STEWART'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
STEWART, of Limehouse, in the County of Middlesex, Builder, send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twenty-sixth day of
January, in the forty-eighth year of His reign, give and grant unto me,
the said William Stewart, my exors, admors, and assigns, His especial licence,
full power, sole privilege and authority, that I, the said William Stewart, my
exors, admors, and assigns, during the term of years therein mentioned, should
and lawfully might make, use, exercise, and vend, within England, Wales,
and the Town of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVE-
HENTS IN MAKING BRICKS AND TILES;" in which said Letters Patent there is
contained a proviso obliging me, the said William Stewart, by an instrument
in writing under my hand and seal, to cause a particular description of the
nature of my said Invention, and in what manner the same is to be performed,
to be inrolled in His Majesty's High Court of Chancery within one calendar.
month after the date of the said recited Letters Patent, as in and by the same,
relation being thereunto had, inay more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
William Stewart, do hereby declare that the nature of my said Invention and
the manner in which the same is to be performed are particularly described
and ascertained as follows, that is to say :-
In the Drawings hereunto annexed Fig. 1 represents, by a shaded vertical
section, machinery for making bricks and tiles, in which my said improvements
are introduced and applied; and Fig. 2 represents the same machinery by
shaded vertical section or view taken in a direction at right angles to that
line of sight to which Fig. 1 is referable; and Fig. 3 represents a considerable

page_text: part of the same machinery by a shaded view, in the manner of a ground plan;
and Fig. 4 represents a less considerable part of the said machinery in the
manner last mentioned; and Fig. 5 and 6 represent the particular structure of
the moulds for making bricks, and of the chain or connecting parts by which
the same are carried, as is hereafter more fully set forth; and throughout the
whole of the said Drawings the same letters of the alphabet are applied to
denote the same parts or things, namely:-The letter A denotes the frame-
work of the machinery. B denotes arms or bars, to which the force of horses
or of men being applied, a rotation will be given to C, the axis of a pug mill,
and the upper part of the said axis moves in gudgeons or sockets, and the
lower part thereof is supported and steadied in its place by friction rollers at D
upon the branch piece E, as is shown in Figs. 1 and 3. F represents the tub
or vessel of the pug mill, in which the clay or material is worked and prepared
by the action of the knives, cutters, or arms G, and the said tub or vessel
is open at bottom so as to afford a duly fitted passage for a series of moulds II
(for making bricks or tiles), which are fastened upon or do by their construction
from the parts of an endless chain, to be carried by the lanterns or leading
frames K and I, which revolve upon their respective axis, and to be supported
in its course beneath the pug mill by the platform of rollers L, and the said
chain and the moulds affixed thereto or forming parts thereof is made to
revolve or circulate in the direction of the small arrows by means of an
apparatus of wheel work M, forming a communication between the first mover
and one of the said lanterns or leading frames K; or otherwise the said
communication may be made by a strap, chain, or in any other well-known
manner, according to the circumstances of convenience or advantage which
the nature and magnitude of the intended machinery or of the first mover may
produce or afford.
And further, I do so proportion the parts of my said communicating
apparatus that the velocities of the rotation in the púg, mill, and of revolution
or circulation of the chain and moulds II, shall be such as shall upon trial be
found adapted to produce or turn out a well manufactured article with suffi-
cient dispatch. And moreover, I do vary the said proportion by changing the
wheels or parts thereof by trial, according to the nature of the materials and of
the work to be performed. And the operation or manner of working the said
machinery is as follows:-The clay or material is to be put into the pug mill,
and motion then given to the machine, and in consequence thereof the moulds
beneath the mill will be filled, and will pass out beneath an edge or striker at
the inner face or side of the pug mill which serves to finish the tops of the
bricks. As soon as any one of the collateral rows or moulds arrives at the

page_text: position P, an attendant applies a board upon that row, and keeps it so applied
until the said row shall have arrived at or about the position Q, at which time
the bricks quit or fall out of the moulds, and are received by the said boards,
and passed off to another workman, who loads and carries the same away;
and in like manner, by means of a few receiving boards, the first atten-
dant takes off all the bricks upon their arrival at the delivery end of the
machinery; and in case a few of the first rows of bricks should, upon beginning
with new stuff, be found to be not sufficiently worked in the mill, the said
first rows must be returned into the mill, instead of being carried away to be
dried and baked. Letter N represents a roller for keeping the moulds down.
Fig. 5 represents part of the chain and moulds upon an enlarged scale, for the
purpose of explaining the means by which the bricks are made to quit the
moulds with facility upon their arrival at the position denoted by Q.
And farther, I do make the bottom and one side of each side of my said
moulds moveable, or capable of being slided back through a small space.
And I do connect cach of the said moveable parts with the preceding link by
a claw or tooth, or by other known means equivalent to toothed work, or
by any other fit and obvious means, so that whenever any two links, as
P and Q, shall become inclined to each other in the largest angle (or therc-
abouts) which the reaction of the lantern or leading frame K can produce, the
relative motion at the joints shall by means of the said connection draw back
the said moveable sides and bottoms, and by that means cause the surfaces of
the bricks to shift their respective bearings of contact, and readily to quit the
moulds; and that so soon as the inclination shall be done away, and the said
links shall have recovered the right lined position, the said moveable sides and
bottoms shall be returned to their former situations, and the moulds shall
be again in a fit state to receive the respective charges. And I do moreover
declare, that the said parts may be made moveable, as here described, either in
connection with each other, or one or more only of the same may be made so
as to have the said motions, and also that the said parts may be easy and
obvious changes of the apparatus be made to slide forwards instead of back-
wards, and with the like effect.
And to the intent that my said improvements may be clearly and distinctly
seen and apprehended separately and apart from such other machinery as hath
heretofore been in common use, but which, for the sake of perspecuity, it was
necessary that I should here insert and describe, I do hereby further declare
that my said improvements, as herein before described, do consist,―
First, in supporting the axis of the pug mill so as to leave its lower part at
liberty to act beneath the supporter; and,

page_text: Secondly, in connecting the series of moulds with the first mover, and
producing a regular correspondence of action between the mill and the said
moulds; and,
Thirdly, in carrying the moulds to circulate by means of or in the manner of
an endless chain upon polygonal lanterns or leading frames, which are equi-
valent to rollers; and,
Fourthly, in causing the moulds to change the relative situation of their
parts so as to deliver the bricks or tiles more readily, and afterwards to resume
their former situations.
And farther, I do declare that the making of tiles is performed in the same
manner as that of bricks, but that the form of the moulds will for this purpose
be required to be quite different, as any competent workman will readily
understand without farther instructions; and that I do use my said improve-
ments in conjunction with the machinery commonly used for making bricks
and tiles and with each other, as is herein set forth, or as may be found bene-
ficial and convenient in any other manner, and that I do also use my said
improvements separately and apart from each other in such cases as I am or
may be induced to do the same from the convenience or advantages to be
derived from so doing; and,
Lastly, that machinery for making bricks and tiles with my said improve-
ments may be worked by animal strength, or by any other known first
mover, and by methods of connection and application which are sufficiently
well known to all operative men.
In witness whereof, I, the said William Stewart, have hereunto set my
hand and seal, the Sixteenth day of February, in the year of our Lord