rbarism which lies within the province
of an intelligent and active conductor to abolish. If a choral or
instrumental piece is performed behind the scenes, without accompaniment
from the principal orchestra, another conductor is absolutely essential.
If the orchestra accompany this portion, the first conductor, who hears
the distant music, is then strictly bound to _let himself be guided_ by
the second, and to follow his time _by ear_. But if--as frequently
happens in modern music--the sound of the chief orchestra hinders the
conductor from hearing that which is being performed at a distance
from him, the intervention of a special conducting mechanism becomes
indispensable, in order to establish instantaneous communication between
him and the distant performers. Many attempts, more or less ingenious,
have been made of this kind, the result of which has not everywhere
answered expectations. That of Covent Garden Theatre, in London,
moved by the conductor's foot, acts tolerably well. But the _electric
metronome_, set up by Mr. Van Bruge in the Brussels Theatre, leaves
nothing to be desired. It consists of an apparatus of copper ribbons,
leading from a Voltaic battery placed beneath the stage, attached to
the conductor's desk, and terminating in a movable stick fastened at one
end on a pivot before a board at a certain distance from the orchestral
conductor. To this latter's desk is affixed a key of copper, something
like the ivory key of a pianoforte; it is elastic, and provided on the
interior side with a protuberance of about a quarter of an inch long.
Immediately beneath this protuberance is a little cup, also of copper,
filled with quicksilver. At the instant when the orchestral conductor,
desiring to mark any particular beat of a bar, presses the copper key
with the forefinger of his left hand (his right being occupied in
holding, as usual, the conducting-stick) this key is lowered, the
protuberance passes into the cup filled with quicksilver, a slight
electric spark is emitted, and the stick placed at the other extremity
of the copper ribbon makes an oscillation before its board. The
communication of the fluid and the movement are quite simultaneous,
no matter how great a distance is traversed.

The performers being grouped behind the scenes, their eyes fixed upon
the stick of the electric metronome, are thus directly subject to the
conductor, who could, were it needful, conduct, from the middle of the
Opera orchest