IMPROVEMENTS IN THE CONSTRUCTION OF ROOFS AND OTHER PARTS OF BUILDINGS."
Year: 1874

page_text: LETTERS PATENT to William Henry Lascelles, of Bunhill Row, in the
County of Middlesex, Builder, for the Invention of "IMPROVEMENTS IN
THE CONSTRUCTION OF ROOFS AND OTHER PARTS OF BUILDINGS."
PROVISIONAL SPECIFICATION left by the said William Henry
Lascelles at the Office of the Commissioners of Patonts, with his
Petition, on the 3rd July 1874.
"
I, WILLIAM HENRY LASCELLES, of Bunhill Row, in the County of
Middlesex, Builder, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE CONSTRUCTION OF ROOFS AND OTHER PARTS OF
BUILDINGS," to be as follows :—
My Invention relates more particularly to an improved mode of con-
structing in wood the curvilinear or arched framings for the roofs of
horticultural structures, such as greenhouses or conservatories, but is
also applicable to constructing the roofs and other parts of other
ouildings.

page_text: The ribs which form the framing of the arched or curved roofs of
horticultural structures aro usually made of iron, in consequenco of tho
facility with which the material can be bent to the proper shape. Wood
however is a preferable material for the construction of horticultural
buildings if it can be brought into the proper form.
The main feature of my Invention consists in a novel mode of con-
structing in wood curved ribs which may be used to form the arched
framing of conservatories and other horticultural structures.
In carrying out my Invention I form the rib of three thicknessos of
wood, the lowermost of which forms the head, the second the body of the
rib, which is grooved on its upper side to receive the third piece, which
is simply a narrow piece set on edge and fixed in the groove of the
middle piece, so as to leave on each side a ledge which will form a rebate
for the glass. These three pieces having been temporarily connected
together are placed in a steam bath for the purpose of softening the
wood, and while still in a hot state the wood may be bent to any desired
curvc. If the three pieces were originally (and when straight) of the
same length the ends of the outermost or top one will not (when the
three are bent) reach to the end of the others. Step joints will therefore
be formed, and the parts may be secured in place by means of cross
bolts or pins passing through all three. A second piece of the rib formed
in the same manner may be joined to the end of the first, and will form
a butt joint, the ends of the several members of the ribs underlapping or
overlapping the ends of the members of the other piece, so as to form
break joints. In this way ribs of any length and to any curvature may
be made, and will be found to combine strength with lightness.
Straight pieces with curved ends may be used with advantage to form
a protection for peaches and other wall fruit trees.

page_text: In the accompanying Drawing Fig. 1 is a side view of a compound
wooden arched rib suitable for conservatory roofs, and Fig. 2 is a cross
section of the same; Fig. 3 is a diagram shewing the kind of roof for the
construction of which arched ribs of the kind shown at Fig. 1 aro
intended to be employed.
The rib is formed of three pieces or thicknesses of wood A, B, C. The
lowermost piece A is made cylindrical and forms the bead; the second
piece B, which is rectangular in cross section, forms the body of the rib.
This piece B is grooved on its under side to fit the bead A, and on its
upper side to receive the third piece C, which is simply a narrow fillet
set on edge and fitted into the groove made for it in the middle picco B.
A ledge is thus formed on each side of the fillet, and constituting
rebates a, a, for the glass covering. The three pieces A, B, C, con-
stituting the rib having been temporarily fitted together are submitted
to the action of a steam bath for the purpose of softening the wood, and
while still in a hot state the wood is bent over a suitably shaped mould,
and retained in contact therewith in any approved manner until it is
cold. While the wood is held down to the mould I secure the parts
composing the compound rib together by the application of wood
screws b, dowels, or their equivalent, and I thus ensure the rib retaining
its curved form. It will be understood that by thus curving the
compound rib the three pieces composing it will so arrange themselves
as to counteract the tendency which one or other may possess to return
to its original shape, and thus a rib is obtained whose tendency to warp
will be minimised if not entirely neutralized.
:
-
When a long length of rib is to be formed by joining together two or
more pieces of the compound curved rib formed in the manner described,
I provide for long laps of the members composing the rib so as to
ensure strong lap joints, but in general I prefer to form the ribs in con-
tinuous lengths.
.
In making my compound ribs I may use any desired number of picces
or members to compose the rib, claborating or simplifying the same to
suit varying circumstances. In this way ribs suitable, for example, for
carrying zinc or other metal covering may be made of any desired
curvature and span, and they will be found to combine strength with
lightness and elegance.
In order to form a protection for peach and other wall-fruit trees I
propose to form the compound curved ribs, as shewn at Tig. 4, in which

page_text: example the bead is omitted, that appendage which adds both strength
and beauty to the rib not being in this case required.
---
Having now set forth the nature of my Invention of "Improvements
in the Construction of Roofs and other Parts of-Buildings," and explained
the manner of carrying the same into effect, I wish it to be understood
that under the above in part recited Letters Patent I claim, the manu-
facture of compound curved ribs, in the manner and for the purpose
above described.
In witness whereof I, the said William Henry Lascelles, have
hereunto set my hand and seal, the Second day of January, in
the year of our Lord One thousand eight hundred and seventy-
five.