A wonder camera is a sort of magic lantern, so contrived as to enable one to use opaque objects for projection upon the screen instead of glass transparencies. For example, if a ]photograher wishes to show his customer how an enlargement from a carte will look, he simply has to put the carte in the wonder camera, and "throw it up." Many enlargement-scales may be made in this way. It consists of a wooden box, with a top made of tin or sheet-iron; the chimney is made of the same material. The lens is the same as used upon a camera for making photographs. At the back of the box (as will be seen by reference to the elevation and plan, Figs. 2 and 3) are two doors placed upon hinges.

When the box is in use, the door e is kept closed. The other door consists of two parts placed at right angles to one another the object of this is to fill the opening in the door e while the pictures are being attached to c; when c is swung into position opposite, the lens, placed at b d, is carried to one side. If stereoscopic views are to be shown, a slit may be cut at e, through which they may be inserted without opening the box. The door e should be cut off a little at the bottom, so as to admit air. The light is placed at h, as nearly opposite the picture as possible. It should be a strong light; an ar-gand burner is the best. At the back of the light is a piece of tin, bent into the form of a reflector. Fig. 3.

Fig. 1.

Fig. 2. A Wonder Camera

The light coming from h strikes c, and is reflected through the lens upon the screen. The plan of the box is represented with the top removed. No dimensions are given, as they will depend upon the focal distance of the lens and height of the light. Care must be used to have the distance from the lens to c when closed equal to the focal distance.

Fig. 3.