Grove's dictionary of music and musicians

472 SIRilNE, LA SIEMEN
main axis, with two dials for registering the
number of rotations in a given time. This
form has been faithfully reproduced in every
manual of Physics up to now.^ The name is
said to have been somewhat fancifully, and
indeed incorrectly, given it from Homer's Sirens,
on account of its property of singing under
water. It is true that if water be forced through
it after the fashion of the Turbine, a buzzing
or humming sound is produced. Seebeok and
others effected material improvements, but the
only two which need special notice are the
instruments constructed by Helmholtz and
Rudolph Komig respectively. The former is
figured and described in that author's Tonempfindungeii,^
and consists essentially of two sirens
united on a single axis, each disc of which
possesses four rows of holes susceptible of being
separately opened, thus giving means for producing
a large variety of intervals.
The upper wind-chest, whichlooksdownwards,
can be rotated on its feeding-tube so as to bring
about varying changes of phase between the two
discs. With this instrument Helmholtz succeeded
in producing excellent results, using a
small electromotor for driving it at a uniform
rate.
The Siren of M. Rudolph Kcenig of Paris is
a far more imposing instniment. It was made
for Vf. Spottiswoode, Esq., P.E.S., was exhibited
by the writer at the British Association
meeting at York in 1881, and is now in the
physical laboratory of the College of Science at
Bristol. It is furnished with more than a dozen
rotating discs of different kinds, which fit on
to a vertical spindle, above a wind-chest of large
size fitted with a keyboard of eight notes. A
strong clockwork actuated by heavy weights
forms the motive power, and an ingenious
counting apparatus is made not only to record
the number of rotations, but also to set going
automatically a watch movement, and thus
obtain by one motion of the observer's hand
the speed of the disc, and the time of the
observation. By properly computing the rings
of perforations, the harmonic series is given by
one disc, and the enharmonic scale by another.
Indeed there is hardly any law of musical
acoustics which it cannot be made to illustrate.^
For purposes of demonstration the siren is
excellent, and also for the illustration of perfect
liiusioal intervals ; but fortheacouratedetermination
of absolute pitch it is far inferior to Lissajous's
optical method ; and still more so to the
tuning-forkmethod, described under Scheibler,
and to Prof. M'Leod's Cycloscope. w. h. s.
SIRENE, LA. Opera-comique in three acts ;
.words by Scribe, music by Auber. Produced
at the Opi5ra-Comique, March 26, 1844. In
I Deschanel, jVot. P7tiIo