s placed in the lantern, and in interrupt the light beam, to show the effects of inter- Two images of the aperture of the card will appear on front of it is held a strip of plate glass. So long as the mittent light on moving objects. the screen, showing that the ray has been divided or glass is… … wearied by viewing the white spot on DOTTBLE BEEBACTION. in the field of the lantern. The changes from blue to the screen, the card is released, and the pink are very pretty. The change begins at the outside. rubber withdraws it from the lower semicircular aper- for the spar may be arranged as…
