Year: 1879

EDISONs NEW TELEPHONE RECBIvER-DIsPENs-


ING WITH THE ELECTRO MAGNEr-FRIcrIoN


ON A CYLINDER OF CHALK VIBRATING AN EN-


LARGED DIAPHRAGM.


The Cunard steamer Algeria sailed for Liverpool
yesterday. having on board Mr.. c. P. Edison. who
has taken with him Of the greatest inventions Of
the age. On learning that the Professor had
cecded in perfecting q great improvement in the
telephone receiver, HERALD reporter went to Menlo
Park to learn the nature Of the instrument Pro-
fessor Edison received the reporter very cordially
and at once set about giving him all the details Of
his wonderful invention. He said he discovered the
principle Of the electro-motograph five or six
years ago. but did not apply it to the telephone
ceiver until quite recently.


THE APPARATUS.


The description Of the apparatus is as follows =
diaphragm Of mica four inches In diameter is held
in suitable framework. A hand crank is made to
rotate small chalk cylinder previously impreg-
mated with the proper chemical solution), with a
continuous forward motion directly outward from
the face of the diaphragm One end Of q metal bar
is fastened to the centre of the diaphragm and the
other end rests upon the chalk cylinder being held
down very firmly by spring. The circuit is made
from this metal bar, through the chalk cylinder
70 the base. As the cylinder il rotated either
by hand other power the friction between tie
metal bar and the chalk cylinder very considerable.
and tlle diaphragm is drawn or bowed outward tow
ard the cylinder. This operation Ia purely me-
chanical and local. When the electric waves are
transmitted from the distant station by the speaker
(who Edison's carbon transmttcr) the wire
to the receiver each wave as 1t passes through the
chalk cylinder effects by electrochenical decompo-
friction between the bar and the cylinder. ac-
cording as the wave may be a strong
the freeing Of the diabhragm permitting it to re-
gain it's normal position Thus series OF electric
waves, with the alternate space between, effects
vibration of the diaphragm in perfect accord with
the voice Of tho speaker. the action being
solely electrical and chemical The element
of time 10 not factor as in the electro
magnetic instrument where. as is well known.
pcrceptble degree Of time is requisite for
charge and discharge In this new telephone appa-
ratus Edison dspenscs entirely with the mag
net, heretofore used On all telephone receivers sub
stitutng the electro-motograph principle. This. by
very much larger diaphragm than is possible with
the electro magnet. thus giving greater volume of
s SOUND ana ooviatng the necessity lor holding the
speaker is transmitted to the distant station
without the loss Of volume. In fact. at
times, with o very considerable increase. the
telephone speaks louder than the person talking ut
the transmitting station. 1t also produces the high
est musical notes with the same perfection a. the
lower ones, something that was found impossible in
the old machine These points of superiority over
the electro magnet due to the fact that while in
the electro magnet tho electric constitute the
force which vibrates the diaphragm of the receiver
in the new machine they only control it, the force
used being strictly local. either the power of hand or
clockwork.


IN THE LABORATORY


The two instruments taken TO Europe by Mr.. G. p
Edison were tested at the laboratory on Tuesday
night, and found to work in most admirable
ner. They will be used by Professor Tyndall during
his lectures Professor Edson's inventions. The
reporter shown all the interesting features OF
the laboratory by OF the assistants. Everywhere
could be the implements used by the Professor
in his experiments tho electric light Mr..
Robinson is ut present hard at work
manuiacturins two large Photographs one
to be presented to the Emperor OF
Brazil and the other to the Emperor of Germany.
The for the latter parsonage is nearly complete.
and now and then gave evidence of its existence by
shricking out whenever rcvolvcd the words OF Ham
let's soliloquy ITO be not 10 be- that is the qucs
ton"


Regarding the electric light, Professor Edison is
slowly but surely reaching the perfection he aims
at. lie IL now completing the mechanism of his
lamp. with view TO its adaptation to public and
private lighting by electricity.