Untitled

58 MODERN MAGIC LANTERNS.
proper position. Slides, for a reason to be given hereafter,
have to be inserted upside down, and as the most careful
lanternists are but mortal, a time is sure to come when a
slide gets in the right way up, and the picture on the
screen is upside down, a fact which is first conveyed to the
attention of the lanternist by the sight of the screen. This
could very well be guarded against by some arrangement by
which the slide can be seen in position, but before it enters
the lantern.
The tube which carries the objective should be provided
with at least one telescope joint, so that lenses of different
focus can be used. As a rule the tubes are made to suit
lenses of about 6-in, focus, but should certainly be able to
carry a 9- or even a 12-in. lens. The draw motion should be
smooth, but not too easy, the lens being held with sufficient
firmness to admit of final focussing with the rack and
pinion with which it is provided, without the slightest
motion of one tube in the other.
On the design of the lantern body depends to a great
extent its portability. The usual form is not a particularly
Fig. 48. THE MATTHEWS' LANTERN.
portable one, but with a little modification this desirable
feature can be largely introduced ; the popularity and convenience
of the limelight having led to a very great
decrease in the size and cumbersomeness of lanterns. This
is seen to its greatest extent in Fig. 48, which represents
THE LANTERN BODY.
the Matthews' lantern, an instrument capable of giving as
large and brilliant results as any single lantern made, and
packing into a box which acts also as its stand, the weight
of the whole being but ten pounds. There are other patterns
obtainable also in which compactness has been carried almost,
if not quite, as far as in the "Matthews," and with no loss
of efficiency.
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