ges of harmony the player
stops the vibration of the strings with his hands, but, in quick
modulations, this method is not feasible, and the mixture of one chord
with another produces a discordant effect. It follows that more or
less rapid figures can only be realised clearly and neatly in the
upper register of the harp, where the strings are shorter and harder
in tone.

As a general rule, in the whole range of the harp:

[Music: C1[flat]-F7[sharp]]

only the notes of the first to the fourth octave are used; the extreme
notes in both compasses may be employed in special circumstances, and
for doubling in octaves.

The harp is essentially a diatonic instrument, since all chromatic
passages depend on the manipulation of the pedals. For this reason the
harp does not lend itself to rapid modulation, and the orchestrator is
advised to bear this fact in mind. But the difficulty may be obviated
by using two harps alternately.[10]

[Footnote 10: A chromatic harp without pedals has now been invented in
France (Lyon's system), on which the most abrupt modulations are
possible. (Translator's note.)]

_Note._ I would remind the reader that the harp is not
capable of double sharps or double flats. For this reason,
certain modulations from one key to another one, adjacent to
it can only be accomplished enharmonically. For instance,
the transition from _C_ flat, _G_ flat or _D_ flat, major to
their minor subdominant chords or keys is not possible owing
to double flats. It is therefore necessary to start
enharmonically from the keys of _B_, _F_ sharp or _C_ sharp,
major. Similarly, on account of double sharps, it is
impossible to change from _A_ sharp, _D_ sharp or _G_ sharp,
minor to their respective dominant major chords or keys; _B_
flat, _E_ flat and _A_ flat, minor must be the
starting-points.

The technical operation known as _glissando_ is peculiar to the harp
alone. Taking for granted that the reader is conversant with the
methods of acquiring different scales by means of double-notched
pedals, it will be sufficient to remark that _glissando_ scales
produce a discordant medley of sound owing to the length of time the
strings continue to vibrate, and therefore, as a _purely musical_
effect, _glissando_ can only be used in the upper octaves, quite
_piano_, where the sound of the strings is sufficiently clear, yet not
too prolonged. _Forte glissando_ scale