PRODUCING THE OPTICAL EFFECTS KNOWN AND CALLED THE DISSOLVING SCENES BY MEANS OF A NEW OPTICAL ADAPTATION FOR THAT PURPOSE
Year: 1877

page_text: LETTERS PATENT to Henry Keevil, of No. 1, Edward Street, Bath, in the
County of Somerset, for the Invention of "PRODUCING THE OPTICAL EFFECTS
KNOWN AND CALLED THE DISSOLVING SCENES BY MEANS OF A NEW OPTICAL
ADAPTATION FOR THAT PURPOSE."
Sealed the 31st July 1877, and dated the 8th June 1877.
COMPLETE SPECIFICATION filed by the said Henry Keevil at the Office of
the Commissioners of Patents on the 8th June 1877.
HENRY KEEVIL, of No. 1, Edward Street, Bath, in the County of Somerset.
"PRODUCING THE OPTICAL EFFECTS KNOWN AND CALLED THE DISSOLVING SCENES
BY MEANS OF A NEW OPTICAL ADAPTATION FOR THAT PURPOSE."
An Invention or improvement in the construction of the optical arrangement
called the dissolving scenes lantern or lanthorns, with the main object of producing
the optical effects known and called the dissolving scenes and effects by means of
a new optical arrangement or adaptation, and which arrangement of purpose calling
the Newtonian lanthorn.
The purpose of the Invention is to produce the same optical effects called dis-
solving the scenes by using only one light, burner, or jet, and one lanthorn only,
instead of as hitherto done, by using two lights, burners, or jets, and lanthorns.
The mode by which I accomplish the above is as follows:-Fig. 1, T, T, are the
sectional sides of a lanthorn of either metal or wood, the whole drawn to a scale of
6 inches to the foot, I adapt a prismatic lens, the sectional form of which is shewn'
at C and having its diagonal surface D'silvered, or a plane right-angled prism of
glass having a lens or lenses fitted to it for the adjustment and focusing of the
pictures placed in the stage at O, and focused by means of the nut of the pinion and
rack P, and to carry on the rays of light passing through the condensing lenses
properly placed as shown at B, B, to take the light emanating from a burner A for
that purpose.
A modification of the above described and the same optical effects may be pro-
duced by using a plane glass silvered speculum or metallic speculum with adjusting
lenses adapted for focusing the scenes, as shewn at Fig. 4. In either case my
Invention consists in placing the arrangement above named within the converging
rays of light after passing through the condensers from the burner, as shewn at C,
[Price Adl

page_text: and before they cross at a focal point, so as to intercept those rays and turn them in
a direction nearly at right angles in order, to make the light cover and occupy the
same place on the disc as that from the usual direct through or front optical
arrangement shewn at E-the complete adjustment being accomplished by an
adjusting screw and spring connected with the frame of the prismatic lens, as shewn
at F.
The above described optical arrangement which I claim as my Invention or
adaptation when used in connection with any of the usual well-known levers and
shutters hitherto in use will produce the effects known as dissolving scenes from
one light burner or jet only, and by the use of one lanthorn only. In order to
produce the best effects. I recommend that the side of the lanthorn G to which my
prismatic arrangement is attached be bent inward to an angle of about 9° degrees
with the front, as shown in the Drawing at H, and in order to produce the dissolving
effects by the above optical arrangement I affix the lever I at any convenient place
such as at J, and to move on a point at K, the position of the said lever and
shutters being shown by the dotted lines. A shutter is fixed at the end of the
arm L to work and cover the rays of light emanating from the prismatic lens at C,
and another shutter M-is placed at the end of the arm N to work and cover the rays
of light emanating from the direct through optical arrangement at E, and by work-
ing the lever either up or down, the desired effects can and will be produced. And
when the light used for the purpose is that known as the lime light or oxy-calcium
light, then in order to produce a uniform intensity of light all over each circle or
'disc, of course the burner A and the lime to swing on a centre W or pivot, such
pivot having a screw abovo it at X, Fig. 5, for adjusting the height of the light, and
by connecting an arm Y of the burner A. with the rod Z and with the levers shown
at V, Fig. 2, the same is made to turn or face alternately opposite to the condensers
B, B, or U, U, as may in turn be required.
Having now described and particularly ascertained the nature of my Invention,
and in what manner the same is to be carried into effect, and used, I would observe
in conclusion that what I consider to be novel and original in its application to
the above purpose and therefore claim as secured to me by the said Letters Patent
is,-
First. The arrangement, combination, and application of a prismatic convex lens,
or a plane right-angled glass prism, or plane silvered glass, or metal speculum with
lenses adapted to either modification in the manner herein-before described and
illustrated, so as to intercept and turn the rays of light passing through and from
the condensing lenses, and to render the one light or burner available for producing
the effects on a disc known as dissolving scenes.
And, Secondly. By arranging the burner carrying the lime for producing the
light to turn or swing on a pivot, so as to cause the flame alternatively to face ench
pair of condensers as may in turn be required; the meaning I attach to the words
prismatic lens is that of a glass right-angled prism having one of its surfaces R,
Fig. 3, formed convex, and of such a radius as will cause it to magnify the pictures
to a similar extent as that produced by the focusing lenses of the front arrange-
ment S, S, in the manner herein-before explained; the prism may also be made
achromatic in the usual well known way if required.
.In witness whereof, I the said Henry Keevil, have hereunto set my hand and
seal, this Seventh day of June, in the year of our Lord One thousand eight
hundred and seventy-seven
HENRY KEEVIL. (L.S.)