The Scranton tribune. [volume] (Scranton, Pa.) 1891-1910, 1897-04-24
From the New York Times.

son Medical college Dr. henry - CHdp-
man talked of the voice in speech and
singing and told some interesting fun
damental facts, among which were
those touching the creation of sound
and how it is received.
Drawing a violin bow across n bell
produces sound. Practically, what oc-
ours is this: The air intervening be
tween the sounding instrument and the
ear is thrown into vibration by tine pen
dulum motion; the tympanic membrane
is thrown into vibration, and, through
the medium of the little bones in the
ear, this vibration is ultimately COM
municated to the acoustic nerve.
Take a long rod, hold it to the head,
scratch the end furthest from the ear.
and you hear. The rod is in vibration
and communicates that vibration to
the ear Whatever the medium-air,
rod, earth-the' cause of any sound is
that this tympanic membrane is thrown
into vibration by the instrument which
causes that sound. The English word
sound implies a cause of the sound
and the hearing of that sound-both
cause and effect-the effect of the sound
being our hearing.
If a particle of air hits the tympanic
membrane very gently the sound is a
faint one, but if that particle of air
pounds the tympanic membrane loud
sound is produced, and the loudness of
sound simply depends upon the force
with which the tympanic membrane is
struck.
The pitch of the sound has nothing to
do with its loudness, because low
pitched sound may be delivered to the
tympanic membrane very gently, and
high pitched one very forcibly.
Sound two organ pipes, one of which
produces sound an octave above the
other. The air from both strikes the
tympanic membrane with the same
force. but there is a difference in pitch.
The air is issuing out of one pipe twice
as rapidly as from the other 1t is pre-
cisely as if there were two pipes full of
water-if it took one minute to empty
the long pipe it would take one-half
minute to empty the short one.
The air vibrates twice as rapidly in
the short as in the long, The long pipe
emits 256 puffs of air in a second, with
a corresponding number of vibrations
in the tympanic membrane. When the
brain is shaken up at that rate it rec
ognizes that sound but when the short
pipe sounds (Which emits 512 puffs a
second) the intervening air and the
tympanic membrane go at the same
rate, and that is pitch.
WHAT PITCH IS.
Pitch is the rate of vibration, the rate
at which the tympanic membrane is
bent in and out. BY a certain instru-
ment we determine the number of vi
brations per second issuing from any
piIN. One pipe corresponds to c of the
piano (256 vibrations per second) The
below that has 12S vibrations per
second, the c below that 81, c below
that 32, the C's above the middle C GO
5l2, 1924, etc, on up to the highest
notes.
The quality of sound is a difficult
subject. Suppose a string of the length
of the E string of the bass viol When
the bow Is drawn across the string the
latter is drawn into vibration, and ac-
cording to the force of the bow sbtroke
we have the loudness or the lowness
The Il of the bass viol (the lowest
string used) goes 43 times in a second
and the tympanic membrane vibrates
that number of times Halve that
strong and it will double it's vibrations
because there is just one-half the
quantity of matter to be moved
Bridging it at one-third its length, the
third will go three times as fast as the
original string, when struck, four times
as fast.
Bridge a string giving out a certain
fundamental note, and the sound goe.
one way in halves. The ear catche:
the not due to the fundamental note
and also, eventually, the note due t
the half of the string is going as 6
whole another portion is going a!
halves, you hear the fundamental note
and you hear the octays above that
one-half the string goes simultaneous
ly with all the string.
A series of instruments called reson
ators, to be applied to the ear is o.
great value in the study of acoustics
One resonator is designed to catch tn,
first octave above the Fundamental
note; another. to catch the third oc
tave above. Using eight resonatoEs on,
may hear the octave above the funda
mental note; the octave above that, tn,
f above that, the G above that anC
finally the b fiat.
Have the + string of the bass viol OF
the corresponding string in the violin OF
piano thrown into vibration and w
hear the note due to the vibration o
the string as a whole. While it is vi
bfatlng as a whole it can vibrate II
halves, which will give the note whicl
is the octave above the fundamental
While the string vibrates as a whole
and at the same time in halves, 1t caI
also be vibrating in quarters, whicl
will give the twelfth above the funda
mental, or q. BY applying the CORE
spending resonator to the ear one will
hear that overtone, and by putting tn
successive resonators to the ear on
will get even eight or nine overtone
from the fundamental note.
Suppose, when the fundamental not
is being heard there Is associated witt
II the half and the quarter; then tn
ear takes cognizance of the funda
mental note, the octave above, and tn
octave above that; but supposing tina
when the fundamental note is sounde
there are perceived simultaneously wit
1t yet other notes. In the first case w
have the first overtone and anothe
overtone associated with the funda
mental and i'm the second case we hav
the fundamental associated with tn
third and with the fourth oVertont
That Is what distinguishes all musica
instruments from each other.
Sounding the e Of the bass viol O
any note at all of fiuto or of a piano
though those notes have the same loud
ness (that is, the tympanic membran
Is struck with the same Intensity, anC
though the rate of vibration is III
same lin the case of the middle c c
the piano 25G to the second), any on