AN IMPROVED METHOD OF CONSTRUCTING AND FORMING CEILINGS AND PARTITIONS FOR DWELLING HOUSES, WAREHOUSES, WORKSHOPS, OR OTHER BUILDINGS, IN ORDER TO RENDER THE SAME MORE SECURE AGAINST FIRE
Year: 1829

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
NORTH, of Guildford Place, Kennington, in the County of Surrey, Surveyor,
send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fourth day of July, in the tenth year of His reign, did, for
Himself, His heirs and successors, give and grant unto me, the said William
North, His special licence that I, the said William North, my executors,
administrators, and assigns, or such others as I, the said William North, my
executors, adiñors, or assigns, should at any time agree with, and no others,
from time to time and at all times during the term of years therein
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, my Invention of
"AN IMPROVED METHOD OF CONSTRUCTING AND FORMING CEILINGS AND PARTITIONS
FOR DWELLING HOUSES, WAREHOUSES, WORKSHOPS, OR OTHER BUILDINGS, IN ORDER
TO RENDER THE SAME MORE SECURE AGAINST FIRE;" in which said Letters Patent
is contained a proviso obliging me, the said William North, by an instrument
in writing under my hand and seal, particularly to describe and ascertain the
nature of my said Invention, and in what manner the same is to be performed,
and to cause the same to be enrolled in His said Majesty's High Court of
Chancery within two calendar, months next and immediately after the date of
the said recited Letters Patent, as in and by the same, reference being
thereto had, will more fully and at large appear.

page_text: NOW KNOW YE, that my said Invention is described and ascertained in
manner following (that is to say):
My Improved Method of Constructing and Forming Ceilings and Partitions
for Dwelling Houses, Warehouses, Workshops, or other Buildings consists in
applying, fixing, and retaining upon or against the woodwork of such ceilings
and partitions certain flat tiles which have been previously moulded and formed
of a composition of plaster with other materials, which, when set and become
dry, will sufficiently resist the action of fire; and every part, of the said ceilings
and partitions, being completely covered over with such composition tiles, will
be effectually protected from the access of fire. My Invention consists in an
improved method, herein-after described, of applying, fixing, and retaining such
tiles, so as to form ceilings and partitions; and I do not lay claim to any
other method of forming ceilings and partitions, by covering the woodwork
thereof with fireproof tiles, except that improved method which is herein-after
particularly described of applying, fixing, and retaining such tiles; nor do I
make claim to any particular composition of materials for making the said
tiles, that composition which I use, and which is herein-after described, having
been before used for other purposes; and also the said composition admits of
great variation, according to the materials which can be procured in different
places; without departing from the nature of my Invention. And in order
that this my Specification may be sufficiently clear to enable competent per-
sons to practice the Invention with the same advantage as I practice the same,
I shall describe the whole process of constructing and forming ceilings and
partitions for dwelling houses, warehouses, workshops, and other buildings in
the manner I practice.
Composition to make the tiles. Take the dust of soft Bath stone,
obtained from the chippings and refuse. small pieces made by masons in
working such stone, grinding the same to powder by a suitable mill of
the kind called runners-on-edge, or rolling stones, turned by a horse or by
other mill work. With the said dust of soft Bath stone mix half as much,
by measure of Dorking quicklime, incorporating the lime and stone dust well
together in a dry state, and to the mixture of quicklime and stone dust add
half as much by measure of plaster of Paris, mixing. the materials well together,
and then beating up the composition with as niuch water as will give.to the
same the consistency of soft-mortar, whichi, when well. worked, is to be put into
moulds, and spread out in smooth layers therein in the form of tiles, which,
if the materials are good and well mixed, will soon set hard .enough to be
removed from the moulds and set up on edge to dry. The composition is
therefore two parts by measure of Dorking lime, three parts by measure of
plaster of Paris, and four parts by measure of dust of Bath stone.

page_text: Moulds for forming the tiles. These moulds are formed on the horizontal sur-
face of a flat table or work bench, Figure 1, which is made very smooth and long.
Straight rails, A, A; B, B, are fixed thereon parallel to each other at such dis-
tances apart as to leave a clear space between them equal to the intended length
of the tiles; usually about twenty-four inches. Other shorter rails, C, C, D, D,
are applied across between the long rails, their ends being fitted into notches
cut into the long rails A, B, the cross rails C, D; leaving clear spaces between
them equal to the intended width of the tiles'; usually fifteen inches. The
thickness or height that the rails A, B, C, D, rise up aboye, the surface of the
table is equal to the intended thickness of the tiles; usually one and a quarter
inches. Each of the rectangular spaces thus bounded on four sides by the
rails A, B, C, D, forms a mould, and the interior edges of the bounding rails
are made to overhang at one side and one end A, D, D, and to underhang at
the opposite side and end D, C, C, of the same mould, in order to form the
tiles with bevilled or rebated edges, that they may fit one to another by over;
lapping, as herein-after described. The inside of each mould is smeared with
oil, and the composition whereof the tiles are made being well mixed up to
the consistency of soft, mortar, is filled into the spaces between the rails, and
certain iron staples (which are for the purpose of fixing and suspending tho
tiles,.as herein after.described,) are then imbedded into the soft plaster near to
the edges of each mould. The staples are pressed down in contact with the
boards of the table, but do not stand up high enough therefrom to reach
through the thickness of the tiles within about one eighth of, an inch. The
composition must be well spread within the mould, and completely up to the
edges of the rails, with a plasterer's trowel or other suitable tool, the upper
surface being worked very smooth therewith, in order to give a finish to that
side of the tiles which is to be downwards if they are applied for a ceiling;
or outwards if they are applied for a partition; and if. it is required to give
the outsides of the tiles à finer surface, a thin layer of fine plaster may be
spread over the same before the mass of the tiles is set. If the lime and
plaster are of good quality, the tiles will soon set in the mounds, and then one
of the long rails A, B, is taken up off the table, and all the cross rails áre
removed, and also by rapping upon the boards. of the table with a hammer in
the spaces between the tiles, the jarring will cause the boards to detach from
the under sides of the tiles, leaving them loose on the table, from which they.
may be removed and set edgeways to dry and harden ready for use. The oil
which was applied upon the boards of the table and. the edges of the rails
which from the mould before the composition was filled in, by filling up the.
pores of the wood, facilitates the separation of the tiles from the boards and rails..
:. The above particulars of the composition for. the tiles, and the manner of

page_text: "
moulding them, form no part of my Invention, except the circumstance of
setting the iron staples in the tiles, by means of which, together with their
rebated or bevelled edges to overlap each other, the tiles are to be fastened
in their places.
.
Figure 2 represents one of the tiles ready for fixing in its place to form
a ceiling or partition. Along two of its sides the edges m, n, overhang, and
on the other two sides o, p, the edges underhang. In the longest of the over-
hanging edges m, two of the iron staples before mentioned were imbedded at
, r, at the time of moulding the tile, the claws or extremities x, x, Figure 8;
of each staple, being buried within the solid substance of the tile, so that the
staples cannot draw out. The width of the tiles must correspond with the dis-
tances between the joists or pieces of quartering or other woodwork forming
the framework for the ceiling or partition; and the tiles are to be applied
against the woodwork so that the sides of the tiles in which the staples are
provided may correspond, as nearly as may be, with the edges of the joists or
pieces of wood framing, as is shewn in Figure 4; and a small iron hook l,
Figure 3, bent like the letter L, is inserted with its short end into each of
the staples r, r, and then the longer end of the hook l, applying against the
side of the joist or piece of wood, is fastened thereto by a nail or two nails, if
need be, and by the said hooked or L-piece the tile is fastened against the
wood. The first row of tiles which is thus applied may require staples at the
two opposite sides of each tile, in order to apply four hooks to fasten each tile,
as shewn at R, Figure 4; but when one row of tiles is thus securely fastened,
the overhanging edges of those tiles will support one edge of the succeeding
row of tiles, whereby two staples and two hooks to each tile will be sufficient
to fasten them securely in their places, as shewn at S and T, Figure 4; or,
instead of four staples and four hooks to each of those tiles that are put up
in the first row at R, the first edges thereof may be fastened by nails or
screws put through the thickness of the tiles into the wood behind or above
the tiles; also, the last row of tiles which is put up must be fastened by
means of nails or screws put through the thickness of the tiles into the wood
behind or above the same; and the heads of such screws or nails being
countersunk deeply into the thickness of the tiles, may be concealed by filling
up with the composition whereof the tiles are made or with plaster. For
forming ceilings in which there are large and deep girders, as shewn in
Figure 5, those girders may be encased or enclosed with tiles of a suitable
width, those at the under side of the girder at a having four staples in each,
at the opposite edges, for the reception of as many hooks or L-pieces to nail
up against each side of the girder. The edges of the tiles should overhang or
project beyond the width of the girder at each side as much as-to-afford a

page_text: lodgment for the lower edges of other narrower tiles Y, which are applied at
the sides of the girder, and may be fastened thereto by nails or screws put
through the thickness of those tiles into the wood. The upper edges of the
narrow tiles Y fit up close beneath the tiles of ceiling. The tiles in each
succeeding row or course that is put up are made to break joints by putting
up a half tile at the beginning of every other row or course next to the wall
or next to the girder, and a whole tile at the beginning of every intermediate
row or course. The tiles, when dried and ready to put up, are easily cut to
any dimension that may be required for those tiles which are to fill up the
spaces at the beginning and end of each surface in a ceiling or partition.
The tiles, haying bevelled edges which overlap each other, leave no direct
fissures through which flame or fire can penetrate, and by fixing one row of
tiles with over-hanging edges, upon or behind which the under-hanging edges
of the next row are inserted, the latter edges are thereby confined and retained
in their places, the opposite or over-hanging edges of the same tiles been
fastened by means of the hooks and staples; and my Invention consists in the
herein-before described method of fixing such tiles, vizt, by inserting staples
into the tiles during the operation of moulding them, placing such staples in
suitable positions to receive hooks or L-shaped irons, for the purpose of
fastening the tiles to the woodwork, and also in forming the edge of each tile,
in which there are staples over-hanging, and the other or opposite edge under-
hanging, in order to interlock and fasten behind the adjacent edge of the tile
next to it.
In witness whereof, I, the said William North, have hereunto set my