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phantasmagoria may be described as a perfected magic lantern, and bears the same relation to its prototype that a shilling telescope bought in the Lowther Arcade does to one of Dollond's or Ross's field glasses. The position of the spectators, too, is different, being on the other side of the scene which receives the magnified pictures, already described when speaking of the magic lantern.

The phantasmagoria lantern is generally mounted on a stand provided with castors so that it may be moved about at will. It consists of a box as represented in fig. 52, inclosing a lamp with a metallic reflector, the bundle of rays being sent through the centre of the tube containing the slide and lenses, as before described. The chimney serves to carry off the products of combustion generated by the lamp. In fig. 53 we have shown the interior of the tube containing the lenses. Between this tube and the body of the lantern there is a space within which slide the glasses whereon are painted the figures and landscapes that are to be thrown on the white screen. The luminous rays given off by the reflector in the interior of the lantern pass through a plano-convex lens placed with the flat side outwards. In front comes the double convex lens, or object-glass, which can be moved backwards and forwards by means