The herald., 1897-03-19
P|C1UR|NG OF THE VOICE
Professor William HaIiock's Re.
markabIe Experiment
VIBRATIONS STRANGE TALE
Facts Revealed by Lighted Gas Jet.
An Ingenious Apparatus
VIBRATIONS STRANGE TALE
Formed of Hollow Metallic Spheres-A rem-
branous Drumhead Brings About
the Necessary Agitation

photographed. Practically the only
thing which science cannot now sue
oeed in producing picture Of is the
soul. The voice. however. can be out
lined by the camera as obviously as If
the observer were listening with all his
might. The result of the experiments
along this line by Prof. William Hallock
who occupies the chair of physics at
Columbia college, have proved the
statement with which this article be-
gins beyond the shadow of a doubt. 1t
has long been believed to be a posi-
biity, but successful accomplishment
has only been brought about by the
most painstaking experiments extend
ing over a long period.
The. photograph in this instance is
that produced by picturing the result
of the vibrations caused by the voice.
Every vibrating body has certain
key note or pitch to which it vibrates.
1t will respond to no other note. 1t is
this fact which enables the construc-
tion of instrumen nts, for the unfailing
law of vibration makes possible abso-
lutte certainty of calculation. 1t Is
necessary in considering Prof Hal
y
stantly in mind. But for this absolute
certainty science could not conduct ex-
periments along this line with any guar
an'tse Of accuracy of result
The apparatus of Prof. Hallock is very
interesting and equally simple. In the
first placs there is series of hollow
metallic spheres Each of these spheres
differs In size. Naturally, each vibrates
to a musical tone, all different. There
are available as it were, all the differ
ent vibrations which go to make up a
melody that pleases the ears of great
and small. Here then is the material
and the next thing is to utilize it. Each
of these balls, or metallic spheres, has
a small hole at one side. Opposite this
hole a membranous drum head is placed.
A lighted gas jet is placed on the farther
side of the drum. This arrangement is
entirely toward the point of vibration.
Therefore, when the air inside the ball
is made to vibrate by the musical
sound corresponding to its tone pitch,
the membrane also ,vibrates. Here is
the curious part of it, The vibration is
promptly communicated to the lighted
gas jet on the farther side of the drum
head The vibration causes the gas jet
to jump and therefore one sound of the
voice is registered in an objective fash
ion.
OF course. while it would be very in
teresting the mere photograph of a sim
gle vibration would be practically value
less from e scientific standpoint. Prof.
Hallock has. however, utilized his meth
cd in a manner that seems destined to
prove of very great value. He arranges
a series of these spheres, drum heads and
lights. so that each one responds to the
tone of a musical scale When the sin
ger strikes c, the c sphere vibrates, and
so on through the gamet. Thus ii may
I1a ant7f hot ha ri ha ho
it means. become matters to be seen
rather than heard In fact person
who is totally deaf could tell, with a
little practice, just exactly what these
gas jets told in the way of music. 1t
has been very common and equally
erroneous expression, from time imme.-
mortal, that one had been to see the
opera. Heretofore it has only been pos
sible to listen to music, but these ex-
periments of Prof. Hallock will evil
IDENTIFY render 1t possible to really see
an opera, and at the same time, hear
it, To see musical sounds is something
few people ever expected would hap
pen, but as has often occurred before,
science has brought about the apparent
ly impossible.
As is well known to musicians and
Psychologists, the pitch OF tone de-
peuds on the number of vibrations or
the rapidity with which the sound waves
follow each other The loudness of a
tore depends upon the extent, the vol
ume. of the sound waves. In the human
voice, the more powerful the air blast
the greater is the extent of the vibra-
tions. Herce. the louder the sound. the
more powerful must be the blast of air
that produces 1t. Therefore, it is plain
to be seen that the more powerful the
note or tone the more noticeable will be
the effect upon the lighted gas jet on the
farther side of the drumhead and
spheres.
The quality of any musical sound de-
perds altogether upon the relative pow
or of the fundamental tone and that of
the over tones or harnonics which ac-
company it. The less the fundamental
tone is disturbed by over torres the
clearer and better Is the quality of the
voice. By means of Professor Hallock's
invention a singer may seat himself be-
fore the apparatus described ard, while
rendering song. may judge by the
haring gas jets exactly the range Of his
voice II, other words. he can descry
every note from the highest to the low
est as each is sung. He also sees by
means of the movement of the gas jets
what over tones are present. ard by
counting these and then comparing the
length of the jump of the jet correspond
ing to the fundamental c with the length
of the jump of the jet corresponding to
the over tones, he manages to gain an
idea of the quality of his voice.
The value of this invention to singers
and to those whose profession 1t is to
try voices is inestimable. Heretofore
it has, of course. bssn possible for a per-
son who was a judge of the singing voice
and a thorough musician to determine
I'M measure whether or no the person
who sought his opinion could really sing.
1t was the judgment formed by knowl-
edge, taste ard long experience which
qualified the expert to give an accepta-
BILE opinion in the matter. When this
opinion has been urfavorable the per-
son whose voice was tested has some
times said II was prejudice rather than
standard of merit which Influenced
their Judge The result of Professor
Hallock's experiments, 1t is believed.
what is practically mechanical test;
test none the less accurate, not less pro-
fessional than the estimate of the ex-
perienced musician would indicate, but
cne that is absolutely infallible.
The person whose voice istested with
the Hallock apparatus can always have
photograph taken thereof, which will
show a power exactly in accordance with
the facts. The possibility of photograph
ing the singers voice also renders 1t pos
sible to give Photographic certificates Of
excellence. One Of these days 1t is likely
to become as common a matter to see a
photograph of a PERSONS voice In a news
paper as it is OF the face. Thus the great
singers Of the world can give ocular ev-