New-York tribune., 1922-04-02
Crystals of Salt
Highly Sensitive
FOrSOundWa aves
Sound of Phonograph Is
Amplificd Through Me-
dunn of Substance When
Attached to the Needle
Pin-Fall Like Thunder
War Uses Likely To Be
Turned to Account in
Peace by Work of Wizard

Did you ever hear crystal speak
Can you imagine an innocent looking
Rochelle salt crystal suddenly burst
ing into song; and spreading the sad
sweet strains of Mimi is tickle heart
ed" throughout the room wherein it
rests
Really, there is nothing foolish
about these questions. l have merely
chosen them as means OF introduce
ing one of the most remarkable de-
velopments III this era of daily won
ders, and, by the way, the subject is
not foreign to radio-phone work, but
in the future may have a great effect
upon it.
We have now come TO the point
where is is necessary to introduce A.
NJ. Nicholson Of the Bell Laboratories,
who probably hes the most peculiar
Job in the world. He it is who acts as
foster father to the crystals nurtures
them to maturity, and then trains
them in the way they should go He
has got them nov to the point where
they will do everything but walk and
eat.
Now the "sineing crystal" is an after
development of an important discovery
that was made during the war. 1t was
found that certain inorganic crystals
when subjected to outside stresses de
ve!oped electricity of very high volt
ege. 1t was further aacertained that
they were extremely sensitive as trans
mtters and sletectors of sound, and the
most sensitive Of them all was the
Rochelle salt crystal.
Used 10 Detect U-Boat
During the war a great deal Of ex
peIimentation was made with them for
the purpose Of developing an extra
sensitive detector for anti-submarinc
work and receiving apparatus was
produced which could detect the whirr
Of submarines propeller under the
water several miles away. Since then
further experimentation has been car
ried on bv Mr. Nicholson in the Bell
La boratories and some phenomenal le-
suits obtained.
Before the crystals can be trained
they have 20 be grown. and this is the
part Of his job III which Nj. Nicholson
takes the kecnest interest. Special watts
for growing the crystals have been IN
stalled and carefully selected nuclei are
placed in them. Some of the crystals
grown in these vats weigh as mucn as
two pounds.
When they are brought into ths
laboratory they are placed IN special
metallic frame, to which wires are at
tached. These frames are so arranged
that a twisting motion can be impaired
to them, and on visit to the labora-
tories this week ! was shown how 1t
was possible to generate 500 volts
in this manner. The assistant to
Mr.. Nichols took one Of the crystals
in his hand and attached the two
wires from, it to volt meter
He then gave the holder twist, and
the needle jumped up until it registered
500 volts.
Sound Is Anplifed
After this experiment I was shown
how the crystals talk. One Of them mad
a phonograph needle attached to its
holder. This was placed on the tone
arm of a phonograph, after the sound
box was rem owed. The needle was then
placed on g record. Wires leading from
the crystal were taken to Il three-stage
nmpliher, OF the same type as used in
radio-phone work, and wires from the
latter were joined up to another crystal.
As soon as the phonograph was
SC1TIeU- LIlt SeCOuu CLt SCdA Dul 81 INV
song Placed in horn, it flooded the
room with the volume of its reproduce
ton.
"I'll show you how the crystal
Dances" said Mr.. Nicholson.
He placed it on the table, and so in
tense was its vibration that it jumped
about in the strangest kind of convul-
sions. He then placed it in his pocket,
and the volume Of sound was large
enough to be heard distinctly, giving
one of the weirdest effects imaginable.
Taking the crystal off the phono-
graph, he next placed it on a sheet Of
paper which was spread over a thick
slab of soft rubber. We were then in
vited to write upon the paper. Every
movement Of the pencil was magnifed
q millionfold and reproduced in tre-
mendous tones by the second crystal.
A pin dropped on the paper is repro
duced as loud as the crash Of thun-
dcrbolt.
The ticking Of watch placed on the
paper is reproduced as loud as the
blows Of 2 village blacksmith's ham,
mer upon the anvil.
"a fly walking over that paper" said
one Of the assistants, would make a
terrific noise"
Although Mr.. Nicholson has had re-
markable success in training the crys-
tails, he has not yet succeeded in train
ing the flies.