ly has a pedal keyboard on which the feet of the
performer play a bass part, this part often sounding an octave (or more)
lower than the notes indicate.

An _eight-foot stop_ on the organ produces tones of the same pitches as
the piano when corresponding keys are struck: A _four-foot stop_ sounds
tones an octave higher and a _two-foot stop_ tones two octaves higher. A
_sixteen-foot stop_ sounds tones an octave lower than the piano, and a
_thirty-two foot_ stop, tones two octaves lower, while some organs have
also a _sixty-four foot_ stop which sounds three octaves lower. This
gives the organ an exceedingly wide range, its compass being greater
than that of any other single instrument, and comparable in both range
of pitches and variety of color only with the modern orchestra.

Modern pipe-organs always have a number of _combination pedals_ or
_pistons_ (usually both), by means of which the organist is enabled to
throw on a number of stops with one movement. The selection and use of
suitable stops, couplers, combinations, etc., is called _registration_.

5. The instruments mentioned at the beginning of this appendix as
belonging to the second class are more familiar in connection with
ensemble playing, being commonly associated with either band or
orchestra.

6. A _band_ is a company of musicians all of whom play upon either wind
or percussion instruments, the main body of tone being produced by the
brass and wood-wind divisions.

Sousa's band is usually made up in somewhat the following
manner: 4 flutes and piccolos, 12 B[flat] clarinets, 1 E[flat]
clarinet, 1 alto clarinet, 1 bass clarinet, 2 oboes, 2
bassoons, 2 sarrusophones, 4 saxophones, 4 cornets, 2
trumpets, 1 soprano saxhorn (fluegelhorn), 4 French horns, 4
trombones, 2 contra-bass tubas, 4 tubas, 1 snare drum, 1 bass
drum, 2 kettle drums, cymbals, triangle, bells, castanets,
xylophone, etc.

7. An _orchestra_ is a company of musicians performing upon stringed
instruments as well as upon wind and percussion. It is differentiated
from the band by the fact that the main body of tone is produced by the
strings.

There are _four classes of instruments_ in the orchestra, viz.,
_strings_, _wood-wind_, _brass_ (_wind_) and _percussion_. In addition
to these four classes, there is the _harp_, which although a stringed
instrument, does not belong in the same group as the other strings
because the manner of producing the to