after which it is continued in a curved conical
prolongation to the cork stopper. The finger holes are disposed in a
geometrical division, and the mechanism and position of the keys are
entirely different from what had been before. The full compass of the
Boehm flute is chromatic, from middle C to C, two octaves above the
treble clef C, a range of three octaves, which is common to all
concert flutes, and is not peculiar to the Boehm model. Of course this
compass is partly produced by altering the pressure of blowing.
Columns of air inclosed in pipes vibrate like strings in sections,
but, unlike strings, the vibrations progress in the direction of
length, not across the direction of length. In the flute, all notes
below D, in the treble clef, are produced by the normal pressure of
wind; by an increasing pressure of overblowing the harmonics, D in the
treble clef, and A and B above it, are successively attained. The
fingerholes and keys, by shortening the tube, fill up the required
intervals of the scale. There are higher harmonics still, but
flautists generally prefer to do without them when they can get the
note required by a lower harmonic. In Boehm's flute, his ingenious
mechanism allows the production of the eleven chromatic semitones
intermediate between the fundamental note of the flute and its first
harmonic, by holes so disposed that, in opening them successively,
they shorten the column of air in exact proportion. It is, therefore,
ideally, an equal temperament instrument and not a D major one, as the
conical flute was considered to be. Perhaps the most important thing
Boehm did for the flute was to enunciate the principle that, to insure
purity of tone and correct intonation, the holes must be put in their
correct theoretical positions; and at least the hole below the one
giving he sound must be open, to insure perfect venting. Boehm's
flute, however, has not remained as he left it. Improvements, applied
by Clinton, Pratten, and Carte, have introduced certain modifications
in the fingering, while retaining the best features of Boehm's system.
But it seems to me that the reedy quality obtained from the adoption
of the cylindrical bore which now prevails does away with the sweet
and characteristic tone quality of the old conical German flute, and
gives us in its place one that is not sufficiently distinct from that
of the clarinet.

The flute is the most facile of all orchestral wind instruments; and
the device