Year: 1886

page_text: I FREDERICK WITTRAM of N° 224 Montgomery Street in the City and County
of San Francisco in the State of California one of the United States of America
Capitalist 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 :-
My Invention relates to an improved slate-cleaner or device for rubbing out
pencil marks from slates and writing tablets and it consists in constructing and
producing a device for such purpose with a water-reservoir, a wet rubber, and a
dry rubber or eraser, substantially after the manner hereinafter described.
The body of the device is hollow to hold water for keeping the wet-rubber
moist. It is produced by bending or striking up with dies a strip of sheet metal
into the form of a flat tube with both ends open, but capable of holding water
when the ends are closed. Into one end of this tube is fitted a block or plug of
some soft substance or material having suitable degree of porosity to take up the
water from the reservoir into which it extends at the inner end and to give off a
suitable quantity thereof at the outer end when such end is pressed against and
drawn over the surface to be cleaned.
The other end of the tube is closed by a block or piece of some harder but also
somewhat elastic material that is fitted tightly in place and is made of sufficient
projection or length to afford a wiper extending beyond the end of the tube, as
well as to constitute a cork or stopper for that end. To fill the reservoir tube this
hard rubber or wiper part is withdrawn and the water introduced through that
end; but instead of having this part removable it may be fixed permanently in the
end of the tube, and an orifice in the side of the tube be provided for a filling
aperture which can be closed by a small cork or plug.
I prefer to make the moist rubber out of a piece of thick felt or some like fibrous
material rolled up into a wad; and to use a block of vulcanized india-rubber for
the dry rubber, or wiper end of the device.
To carry the device in the pocket a cap may be provided for covering the
moist end.

page_text: The following description fully explains the manner in which I construct the said
improvement and produce the same, the accompanying drawing being referred to
by figures and letters,-that is to say:
Figure 1, is a perspective view of the device illustrating the manner of using it;
Figure 2, is a longitudinal section taken across the body; and Figure 3, represents
the parts in detail that go to form the device.
A is the reservoir tube that forms the body of the device, B, is the moist rubber;
and C is the block or piece to be used both for erasing and for drying the moistened
surface over which the other part C has been drawn.
The tube is readily made out of two pieces of sheet metal previously bent or
struck up into the shape shown at A¹ A figure 3 with the sides a, a, so turned up
at a right angle to the face a* that when the two blanks A¹ A¹ are put together
face to face the sides will fit together and hold the two parts at such distance apart
from each other as is required to produce the tube. These sides overlapping are
soldered together by running a soldering iron along the seam.
The porous moistening end of the device I prefer to make out of a strip of thick
felt or like material by rolling or folding it into a wad, and then fix it into the end
of the tube and hold it in place by any suitable means such as by bending in the
edge of the tube.
The block or piece in the opposite end is made of a strip of vulcanized india
rubber or some other suitably hard, non porous and somewhat elastic or pliable
material. It is either permanently fixed into the end of the tube or is adapted to
be removed whenever the tube needs to be filled with water. In the one case, a
filling aperture d, fitted with a cork or stopper, D, is provided in one side of the
tube, and in the other case this aperture is omitted and the part C, can be
withdrawn and replaced to close the tube after the water is poured into the
reservoir.
The cap E to cover the moist-rubber can be used when the device is to be carried
in the pocket.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is―
1. The herein described device consisting of the water holding tube or reservoir A
the porous rubber, B, in one end, and the non porous rubber C in the other end,―the
former constituting a moistening rubber, and the latter serving for a harder drying-
rubber and eraser, substantially as set forth.
2. The combination of the flattened tube A with filling aperture, d, closed by a
stopple, the porous moistener, B, and the non porous drying rubber C, constructed
for operation as described and shown.
1 1
Mana 1000