The waves that play upon the surface of the lake are produced by a slide in a third lantern. This slide consists of glass screens upon which waves are painted. These screens are actuated by three eccentrically mounted rods set in motion by clockwork. The interference with these waves permits ribbons of light, of constantly varying position and width, to fall upon the screen and to give the effect of water ruffled by a breeze. The play of color and intensity of light produced by the revolutions of the earth and its passage through the penumbra and umbra of the moon’s shadow, and the development of full sunlight, are perfectly coördinated to the changing condition of their source, the sun. This part of the illusion is effected by the management of the foot and border lights.
THE PLASTER IMAGE OF THE MOON.
MT. ARISTARCHUS.
