Improvements in or applicable to Slates or Surfaces used for Writing, Drawing, or Making Lines upon by Slate Pencil.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in or applicable to Slates or Surfaces used for
Writing, Drawing, or Making Lines upon by Slate Pencil.
We, WILLIAM HALL, of Stonewell, in the Borough and County of Lancaster,
Surgeon, and RICHARD CAPSTICK, of 18 Bulk Street, Lancaster aforesaid, Tinplate
Worker, do hereby declare the nature of this invention and in what manner the
same is to be performed, to be particularly described and ascertained in and by
the following statement:―
Our invention consists in applying to, or combining with slates or surfaces to be
written or marked upon by slate pencil a roughened or serrated surface preferably
like that of a file, which may be secured to the frame or margin of the slate or surface
to be written upon in any convenient manner, so that upon this roughened, serrated
or file like surface (hereinafter called the file) the slate pencil to be used, may be
rubbed to and fro, to give the required point or sharpness to the pencil.
By this means the file being secured to the slate, is not liable to be lost and is
ready for use at any moment.
Fig. 1 is a face view of an ordinary slate a, with a wood frame b, b', b², and 63,
round it.
One of the files is only required for each slate, but four modes of securing the files
to the frame, are shown in Fig. 1 one upon each side of the frame.
The file is marked c, on each side-on the b, side of the frame it is a thin flat piece
of hardened steel c, of the breadth equal to the thickness of the frame b, and its outer
surface is cut like a file of any required degree of fineness.
The toothed face of the file is sunk a little below the edge of the frame b, (as
shown) and is held at each end in an under cut in the wood of the frame and forced
in with sufficient tightness to be held firmly therein.
On the ', side of the frame the file has a countersunk hole c¹ made through it at
each end, and is sunk in the edge of the frame b', and secured thereto by small
nails c, driven through the countersunk holes as shown in dotted line.
On the edge of the , side of the frame the file is made with a sharp prong c³, at
each end, to be driven into the edge of the wood frame, staple fashion, the two
prongs being shown in dotted line.
On the side of the frame, the file is formed same as that on the ', side of the
frame, but is secured to the flat face of the wood frame ³, by nails or screws &, as
shown.
In the case of surfaces prepared to be written or marked upon by slate pencil
having no frames, the file is or may be secured by rivets or other means to the flat
side near one edge of the surface.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is
The combination of a plate of metal or other suitable material having a roughened,
serrated or file like surface with slates or the frames of slates or with slabs or surfaces
of other material to be written or marked upon by slate pencil substantially as and for
the purpose hereinbefore described and illustrated by the drawing.
Dated this Seventeenth day of December 1890.