A New Magic Lantern Slide.
Year: 1892

page_text: Date of Application, 9th Mar.. 1892
Complete Specification Left, 9th Dec., 1892-Accepted, 14th Jan., 1893
PROVISIONAL SPECIFICATION.
A New Magic Lantern Slide.
I, WILLIAM HAVELOCK_MASON of 8 Harold Terrace Hermitage Road Green
Lanes, Musical Instrument Dealer, do hereby declare the nature of this invention
to be as follows:--
With a solution of saltpetre or other suitable chemical substance or substances, I
write, draw, or print any design upon any unglazed paper or other suitable
Substance, which I mount as a magic lantern slide. I then apply fire to any part
of the said design & put the paper or other substance prepared as aforesaid into
a magic lantern. The said paper or other substance produces on the screen either
darkness or a colour according to the thickness, texture, & colour of the said
paper or other substance. Fire having been applied as aforesaid, the paper or
other substance prepared as aforesaid burns away in the parts drawn, written, or
printed on with the said solution, but remains intact in the other parts thereof.
The result is that the design so written, drawn, or printed as aforesaid, is gradually
reproduced on the screen, in white upon a black or coloured ground according to
the nature of the paper or other substance as aforesaid.
Dated this 9th day of March 1892.
WILLIAM HAVELOCK MASON.
COMPLETE SPECIFICATION.
A New Magic Lantern Slide.
1, WILLIAM HAVELOCK MASON, of 8 Harold Terrace, Hermitage Road, Green
Lanes, Musical Instrument Dealer, 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:-
The invention has for its object the production of a new magic lantern slide
whereby a drawing, writing or other delineation is made, more or less gradually,
to appear upon a screen as though it were being drawn thereon.
In carrying my invention into effect I take a saturated solution of saltpetre
slightly thickened with gum arabic dissolved in water, or a solution or preparation
of other suitable inflammable chemical substance or substances, and with it I write,
draw or print any design, writing or delineation upon an unglazed paper or other
suitable substance which is capable of burning away readily at the parts where the
solution is applied, but which will remain intact at the other parts thereof.
I mount this prepared paper or other suitable substance as a magic lantern slide,
a suitable form consisting of a cardboard "mount" having a square or other
suitably shaped aperture therein and of somewhat similar character to mounts used
for drawings, pictures, &c., on one side of which "mount I cement the prepared
paper or other substance used.
Slides thus constructed are placed in a carrier in a magic lantern, fire is applied
to one or more points of the design and it is then focussed.
The said paper or other substance produces on the screen either darkness or a
colored disc, according to the thickness, texture and color of the said paper or
other substance. Fire having been applied as aforesaid, the paper or other
substance prepared as before described burns away at the parts drawn, written or
printed upon with the solution referred to, but remains intact at the other parts
thereof. The result is that the design so written, drawn or printed as aforesaid, is,
ID 77

page_text: more or less gradually, reproduced on the screen in white upon a black or colored
ground, according to the nature of the paper or other substance used.
I would here remark that the lines of the writing, drawing or other delineation
are preferably made as continuous as possible in order to avoid the necessity for
applying fire thereto at any inconveniently large number of places, but, in order
that the ground may be retained flat when the inflammable composition forming
the design has been consumed, I make a suitable number of spaces in the design so
as to leave at intervals unconsumed cross pieces, which connect the various parts of
the ground securely together and thereby prevent any part thereof from falling out
I would also remark that other suitable solutions or preparations of
inflammable material may be employed in lieu of the preparation of saltpetre herein
referred to.
of focus.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :
1. A magic lantern slide consisting of a sheet of unglazed paper or other suitable
material on which any desired design or matter is written, drawn or printed by
means of a solution or preparation of saltpetre or other readily inflammable
material, substantially as herein described and for the purpose stated.
2. A. magic lantern slide in which a design or other matter is drawn, written or
printed on a suitable ground with a solution or preparation which is readily
inflammable substantially as herein described and for the purpose stated.
Dated this 9th day of December 1902.
טרנו תof ei
WM. H. MASON,
By Harris & Mills,
23, Southampton Buildings, London, W.C., Agents.