CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF GLASS ROOFING FOR GREENHOUSES CONSERVATORIES AND OTHER GLASS STRUCTURES
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by Charles Edward Osborn at the
Office of the Commissioners of Patents on the 9th April 1883.
CHARLES EDWARD OSBORN of N° 9 Angel Court Throgmorton Street in the
City of London Solicitors Clerk CERTAIN IMPROVEMENTS IN THE CONSTRUCTION
OF GLASS ROOFING FOR GREENHOUSES CONSERVATORIES AND OTHER GLASS
STRUCTURES
In this arrangement the principals or Main rafters are fixed in the ordinary way
of constructing either a lean to or a Ridge Greenhouse Conservatory or other
Glassed Structure, at 2. 3 4 or 5 feet from each other as may be necessary or
convenient-across these are fixed horizontal bars or purlins of rectangular section,
into the side of each of which, facing towards the Gutter has been cut a groove about
half an Inch deep and a little more than double the thickness of the Glass intended
to be used these purlins are to be of the thickness and breadth proportioned to the
strength required by the distances at which the principals have been placed, and
both they and the principals may be ornamented or moulded on their under faces
The Grooved top bar or ridge being fixed in its position, a sheet of Glass of the
size intended to be used (say 14 x 16) is then placed in the groove and the first
purlin is brought into position so that the bottom edge of the sheet of glass may
overlap the top face of the purlin about one inch and the purlin is then fixed in
its place by being nailed or screwed to the principals-The sheet of Glass is then
fixed into its place by two copper or zinc nails with broad heads being driven into
the purlin-Care must be taken not to drive these nails too heavily and they may
be furnished with elastic washers under their heads The Second Sheet of Glass
is then put into position by placing it in the groove of the ridge bar in the same
way as the first but at a distance from it of say twelve inches (allowing one inch
for lap on either side) and secured by two broad-headed nails to the purlins as
before The third sheet of Glass is then placed in the groove in the ridge or top
bar resting on and overlapping the two sheets already fixed and the interstice or
space at the bottom of this sheet between it and the purlin is to be filled up with
a narrow strip of glass of the same thickness and two broad headed nails will then
fasten this strip and the sheet of glass to the purlin in the same manner as before
-This arrangement is to be repeated till the whole of the roof is covered in
D

page_text: A sloping groove or depression which has been cut on the top face of each purlin
with an outlet in the centre of each pane will serve to carry off all drip or
condensation water from the inside to the outside
A modification in the above is to make the slit or groove in the horizontal bars
or purlins a little deeper than the thickness of the glass intended to be used and
instead of lapping the edges of the sheets of Glass to butt the sheets against
each other and nail them to the bars or purlins in the same way as already
pointed out and if they are closely butted to each other the rain will not come
through