IMPROVEMENTS IN OR ADDITIONS TO POLES FOR LAWN TENNIS NETS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by Samuel Cleland Davidson at the
Office of the Commissioners of Patents on the 8th May 1883.
SAMUEL CLELAND DAVIDSON of Belfast in the County of Antrim, Ireland,
Merchant, "IMPROVEMENTS IN OR ADDITIONS TO POLES FOR LAWN TENNIS NETS
"
The invention relates to the poles employed for supporting the ends of the net
used in the game known as lawn tennis, and its object is chiefly to provide
convenient means for making fast the net rope to the poles when it is drawn up
to its correct height between them. For this purpose I employ the hereinafter
described lever clutch to which the end of the net rope after passing over a sheave
or grooved wheel on the pole is secured.
The upper part of the pole is slotted to receive the sheave or wheel which is
fitted on an axle over which the net rope is strained and the sheave is so placed
that the distance between its upper edge and the projecting arm of the elbow bar
hereinafter described is exactly equal to the height at which the ends of the net
have to be supported on the poles, this height according to the present rules being
3 feet.
$
The lever clutch consists of a small eccentric disc operated by a lever handle
which causes it to press against a stationary back plate, to which it is attached by
an axle through a projecting snug. The rope to be secured is passed in from the
side between the eccentric disc and the back plate, and the lever handle is then
pressed down, which so tightens the disc upon the rope that it is gripped firmly
at that point until the handle is raised up again.
For the purpose of resisting the strain upon the poles when the net is drawn up
between them I dispense with guy ropes or other fastenings of a more or less
obstructive and troublesome nature and in lieu thereof I attach to the lower end
of the pole what I call an "elbow bar." It is a flat bar preferably of malleable
iron and about 30" long, 2" broad and " thick, and bent in the middle to form a
right angle or elbow.
The pole is preferably made of wood and rectangular in cross section and to its
lower end one arm of the elbow bar is fastened, so that the other arm projects at
right angles from the pole about 15 inches from the point. The attached arm of
the elbow bar may be attached to the pole either above or below the projecting
arm but preferably below, as it then forms a protection and cutting edge to the

page_text: point of the pole which is wedge shaped, the slope of the wedge being altogether
on the opposite side to that on which the elbow bar is attached.
The pole is to be driven into the ground until the projecting arm of the elbow
bar bears firmly along the surface, and the two poles, between which the net is
stretched, should have these arms in direct line between them, in which position
they act as resisting levers to support the poles against the inward pull of the net
rope, and they maintain the poles so firmly in an upright position that even when
the ground is comparatively soft from rain they will stand so, without alteration
for weeks and without any other stays or supports whatever. The projecting arm
of the elbow bar lies so flat along the surface of the ground that it is scarcely
observable and forms no obstruction around the pole.