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80 MODERN MAGIC LANTERNS.
difficult to realise what the combined result of any two
geometrical designs so revolving will be. Very fine patterns
resembling " watered " silk can be got by mounting fabrics
such as netting, muslin, etc., with a clear and well-defined
thread, in such a revolving arrangement, taking care, to
secure the best result, that the two fabrics shown together
are similar.
Revolving slides, on the principle of the chromatrope, are
made having such things as windmills with revolving sails,
acrobats spinning round on a trapeze, fish swimming in a
globe, bees round a hive, etc., for their subjects ; and can be
obtained from most dealers.
The various slides alluded to above can all be shown by
means of a single lantern, but those now to be mentioned
require at least a biunial for their exhibition. With such
an instrument the number of combinations, effects, etc., that
can be obtained is almost unlimited. The simplest of these
is the curtain slide, in which the picture on the screen is
shown with a curtain round it, as if it were on the stage of
a theatre. A balcony or verandah slide is sometimes used
in place of the curtain ; the scene then appears to be viewed
from the interior of a room, looking out over the balcony.
In these and similar effects, the curtain or balcony, as the
case may be, is projected by means of one of the lanterns,
the cther being used to throw the usual slides in the blank
space left for that purpcse in the " curtain " slide. It
should be borne in mind that this entails the use of a great
deal of gas, as both lanterns have to be kept going all the
time.
A carrier has just been introduced by Mr. G. Davenport
in which the screen is darkened during the change of slide
by art opaque curtain, which appears to come down and
mask one picture, rising afterwards and revealing the fresh
slide. Such a carrier, with a curtain or border slide of any
kind in the other lantern, would no doubt give a pleasing
effect.
Akin to these are snow and rain effects. These are
obtained by means of a slide in which a roll of opaque
material is gradually unwound through the lantern. For
snow, the fabric is pierced with little holes, for rain it is
MOVING SLIDES AND EFFECTS.
mr,rked with fine lines. In both these cases the effect is
improved if the slide is not inserted in the lantern in a
perfectly horizontal manner, but is slightly inclined, so as to
give the idea of a little wind. It is important, moreover, if
the illusion is to be of the best, that the light in the lantern
showing the rain or snow slide shall not be too powerful ;
especially is this the case with the rain. The writer
remembers seeing a lantern display in which a poor waif,
seated on a doorstep, was exposed to what was intended to
be a shower of rain. Owing to the operator having, if anything,
a brighter light in the "rain "lantern than the other,
the shower suggested nothing so much as one of white hot
knitting-needles, and the effect on the audience was anything
but what was intended.
Moonlight effects are obtained by means of a biunial
lantern and two slides, the subjects upon each being
absolutely identical as regards outline, but one can be very
much more vigorous than the other. With photographic
slides, which are much the best for the purpose, this
difference can easily be obtained. The first slide, intended
to depict the daylight view, can be made in the usual way,
with the usual amount of density and contrast. The second
slide, however, should be exposed for a little under the
suitable time, and should be developed with a view to
getting plenty of contrast, rather than what a photographer
would describe as a soft result. This second slide must
then be treated with a bath of a deep blue aniline dye, so
as to give it that blue tint usually associated with moonlight
views. Any lights which it is intended shall appear in it,
such as gas-lamps, illumined windows, stars, the moon
itself or its reflection on the water, must then be carefully
picked out so as to leave the slide bare where it is intended
these shall be. The two slides being then most carefully
registered, the daylight picture is first shown, and gradually
dissolved into the moonlight one.
Such effects can be multiplied almost without limit, by
having accurately registered slides and plenty of assistance.
The number of lanterns required rarely exceeds three in the
most elaborate displays, since in nearly every case the effect
at any one time is obtained by the two lanterns, leaving the
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