M. Brandt places alternately, in a continuous line, forty lamps of
ordinary glass, forty of green glass, and forty of red glass, making
a hundred and twenty lamps in all, at the foot of the stage. Each
series of forty lamps forms a separate circuit. The three series can
be lighted independently, or they may be combined, in order to obtain
different effects of color. For example, a delicate rose hue may be
produced by simultaneously lighting the red and the white lamps; a
moonlight effect, by a combination of the white and the green lamps.
In order to pass gradually from the latter to full daylight, it is
only necessary to increase the resistance in the green circuit while
strengthening the current in the white lamps. Moreover, the two sides
of the stage may be lighted independently, because the 120 lamps are
again subdivided into two circuits of sixty each. We may thus have a
moonlight on one side of the stage, while the other side, at the moment
when an actor enters with a torch in his hand, seems to be illuminated
by the reflection from the torch. When the footlights are of gas, a
current of hot air ascends above the whole line of lights, forming a
sort of gaseous wall between the stage and the audience, which often
makes it difficult to hear the actors. This inconvenience is suppressed
by electric lighting, and the opera singers are agreeably surprised at
the great improvement.--_Lumiere Electr._