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The Optical:-Magic Lantern Journal and Photographio Enlarger, 51
Several ingenious forms of carriers have been introduced of late years ; amongst others, that by Mr. B. J. Edwards, which until now has never previously been published. Like the preceding form, the one slide is inserted in the carrier during the time that the other is in front of the condenser, but in this case the
two openings through which
Fic. 28,
the slides are exhibited are not in the same plane, but are set at an angle (Fig. 31):
carrier arrangement, moving with a reciprocal | The slides are introduced at AA, and the carrier action (Fig. 29). The pictures, which are easily | turns on a pivot B, The condensers are shown brought to view by sliding the movable portion | at C.
across the field, are placed in two separate receptacles, the one division being emptied and
Fic. 29%
recharged during the time that the picture in the other is being shown. The method by which the slides are secured in place will be observed in the diagram Fig. 30, which represents the box portion
Fic. 30.
of the carrier. The slides are merely dropped through a slot in the top.
A few years ago Mr. A. Cowan devised and exhibited a means of making a quick change with this carrier. He attached cords to the movable portion, and according to which cord was pulled, so was that particular picture instantly brought into view.
Fic. 31
A mere touch of the finger suffices to swing the one picture out of place, to be instantly replaced by the other. This changer, which is affixed to the lantern by a thumb screw, is very compact and efficient, and it may be worked with equal facility from either side of the lantern. By a lever which may be fastened to the upper part, to which a curtain can be attached, it is a simple matter to completely shut out the light during the momentary period of changing the view, if such be desired.
Self-centreing carriers all work on the same general principle, and that is:—The slide is