lso
to speed long-distance calls from automatic phones through rural
exchanges.
The numbers which can thus be spoken are recorded on talkie films
and those which are to go into use here have already been made, all
by an Irish girl said to have the best voice among the city's
"number, please" girls.
Mr. Grace demonstrated this device by carrying into the audience a
telephone with a long cord connected with a loud speaker on the
stand, which represented central. A member of the audience was
requested to dial a number, and choose 5551-T, the letter T
representing the exchange.
This number the spectator dialed on the phone Mr. Grace carried.
There was no sound but the clicking of the dial. Then, two seconds
later, the loudspeaker spoke up clearly, in an almost human voice,
"5551 T."
As for the recording of the sound films, there is a film for each
of the ten Arabic numerals from zero to nine, and these wound on
revolving drums. The dial on the telephone automatically sets in
action the drum corresponding to the numeral moved on the dial.
Another development which sounds promising for bashful suitors and
other timid souls, enables a person to store within himself
electrically a message he desires to deliver and then to deliver it
without speaking, simply by putting a finger to the ear of the
person for whom the message is intended.
This Mr. Grace demonstrated. He spoke into a telephone transmitter
and his words were clearly heard by all in the audience, by means
of amplifiers. At the same time a part of the electrical current
from the amplifier, representing the sentence he voiced, was stored
in a "delay circuit," another recent invention of the laboratories.
After being stored four and a half seconds this current was
transformed to a high voltage and passed into Mr. Grace's body. He
then put his finger against the ear of a member of the audience,
who heard in his brain the same sentence. The ear drum and
surrounding tissues are made to act as one plate of a
condenser-receiver, Mr. Grace explained, with the vibrations of the
drum interpreted by the brain.
A new magnetic metal, "perminvar," and a new insulating material,
"para gutta," which make possible construction of a telephone cable
across the Atlantic to suppleme
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