IMPROVEMENTS IN GREENHOUSES
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by Thomas Hungate Preston Dennis
at the Office of the Commissioners of Patents, with his Petition, on the
18th October 1865.
I, THOMAS HUNGATE PRESTON DENNIS, of Chelmsford, in the County of
Essex, Horticultural Builder, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN GREENHOUSES," to be as follows:-
My Invention has for its object improvements in the fixings, fittings,
ventilation, and glazing of greenhouses. First, as to the fixings, I attach
iron or other metal eyes on plates to the building or wall against which the
greenhouse has to be placed some few inches below the ridge line. The
ridge or fixing plate (having mortices in it to allow the eyes to project
through) is then fitted up close to the building or wall, and wedges or keys
are passed into the eyes, which force and secure the ridge or fixing plate
firmly to the building or wall. The rafters, end plates, and other parts can
then be attached to such ridge or fixing plate in the usual manner with nails
or screws, and the whole may be removed by withdrawing the wedges or keys.
When the ridge can be brought to the top of the back wall the following
plan may be used:-A metal cramp or holdfast, made of wrought iron by
preference, is made to lay upon the top with one end turned down over the
side of the back wall, the other end to run past and overhang the upright

page_text: line of the back wall on the side against which the greenhouse is to be fixed,
and in this projecting or overhanging part a long hole will be made, and a
knee or angle piece will then be fixed upon the top of such cramp or holdfast
at right angles with it and flush with the upright line of the wall. Or this
knee or angle may be formed out of the solid by punching the said hole on
three sides only, and turning the piece thus punched backward and upward
until it is flush with the upright line of the wall. It is against these knees
or angles that the ridge or fixing plate (which in this case stands partly above
the top of the wall) rests. The cramps or holdfasts will be laid upon the back
wall at distances varying from three to six feet, and when so laid the ridge
or fixing plate (having mortices in it to allow the ends of the cramps or
holdfasts to project through it) is then fitted up close to the wall with part
of its depth standing above the top of the wall. Wedges or keys are then
passed through the long holes of the cramps or holdfasts which force and
secure the ridge or fixing plate firmly to the back wall. The rafters and
other constructional parts can then be attached to the ridge or fixing plate in
the usual manner, and the whole can be withdrawn by removing the wedges or
keys.
The fittings will consist of metal fastenings to support and retain the
sashes in their places, and front mullions to support eaves plate.
The
ventilators in the front and at the apex of the roof are connected by means
of rope or wire passing over pulleys, and thence to a long commecting rod,
which being moved backwards or forward by means of a rack and wheel or
other leverage opens or shuts the ventilators simultaneously. Another plan
of ventilation may be arranged at the lower part of greenhouses by building
the front dwarf brick wall one foot six inches or any other suitable distance
back from the front plate and running out piers at intervals of from three to
four feet to support the front plate, thus forming a space between it
and the wall, which being covered by a hinged or sliding shutter forms the
ventilator.
The glazing I propose to accomplish without the use of putty by having
thin layers of india-rubber or other soft or elastic material covering entirely
the rabbit of the sash bar, the glass being pressed on to its bed by metal
cappings will be secured there either by pins and springs or other suitable
fastening.