ther braces which are made to slide up and
down the zig-zag of cord, slackening or tightening the large hoops, and
with them the vellum, at the will of the performer. Systems of rods and
screws are also used for the purpose. The bass drum is mounted on a
stand when used in the orchestra. The sound is produced by striking the
centre of the vellum on the one end of the drum with a stick having a
large soft round knob composed of wood covered with cork, sponge or
felt. The bass drum cannot be tuned since it gives out no definite note,
but the pitch may be varied, according as a rich full tone or a mere
dull thud be required, by tightening or loosening the braces; the
instrument can, moreover, be muffled by covering it with a piece of
cloth. The music for the bass drum is generally written on a stave with
a bass clef, [Illustration: notes], the C being merely used to show the
rhythm and accents. Sometimes the stave is dispensed with, a single note
on a single line being sufficient. The bass drum has a place in every
orchestra, although it is used but sparingly to accentuate the rhythm.
It is possible to make gradations in _forte_ and _piano_ on the bass
drum, and to play quavers and semi-quavers in moderate _tempo_. A roll
is sometimes played by holding a short stick, furnished with a knob at
each end, in the middle and striking in quick succession with each knob
alternately; two kettledrum sticks answer the purpose still better. It
is understood that the cymbals play the same music as the bass drum
unless the composer has written _senza piatti_ over the part. Wagner did
not once score for the bass drum after he composed _Rienzi_, but Verdi,
Gounod, Berlioz and Sullivan used it effectively. The bass drum was
formerly known as the _long drum_, the cylinder being long in proportion
to the diameter.

The _side_ or _snare drum_ (Fr. _tambour militaire_; Ger.
_Militartrommel_; Ital. _tamburo militare_) is an instrument consisting
of a small wooden or brass cylinder with a vellum at each end. The
parchments are lapped over small hoops and pressed firmly down by larger
hoops. As in the bass drum, these and the vellums are tightened or
slackened by means of cords and leather braces, or by a system of rods
and screws. Across the lower head are stretched two or more catgut
strings called snares, which produce a rattling sound at each stroke on
the upper head, owing to the sympathetic vibration of the lower head
which jars against the