Vermont farmer. [volume] (Newport, Orleans County, Vt.) 1870-1877, 1877-03-30
The Telephone.


ductivo Of many signal blessings to mankind,
can hardly be said to have yet advanced far
beyond its infancy. The nature Of the ele-
ment is still mystery to those who have
studied it most diligently, while from time
to time, novel manifestations of its powers
aud properties excite afresh the wonder and
admiration OF the multitude.
The most recent revelation of its adapta.
biity 10 civilized needs is the telephone.
Tho telegraph flashed intelligence to distant
places by representing there, by signs or
written characters, the manipulations of an
operator at the starting point; but the tele-
phone does the same by reproducing at one
end Of the line, the sounds, vocal and in.
strumental made at the other. So accurately
are those transmitted that distant speaker
can be recognized by the accent and tone of
the voice almost as easily as il standing be-
side the listener. During the FIRST public
exhibition Of the instrument, ballad sung
by young lady at one end of the line, in
Boston, delighted an audience six miles away
at the the other end in Maiden. AT a still
later trial "Auld Lang Syne" and Yankee
Doodle" played upon an organ at one end
Of the line in the Hub" were greeted eight.
cen miles away, at the other end in Salem,
as enthusiastically as either was ever hailed
by iuddled Scot or patriotic New Eng
lander. Still more recently several other
tests, over longer distances and under more
severe conditions, have even more clearly
demonstrated the wonderful capabilities of
the instrument. Nor are loud utterances
only ones that can be transmitted by it. even
low tones and whispers are said TO be audi
BILE over the wires with equal distinctness
The volume Of sound, at the point where toe
message is delivered is equal to that at the
end whence it is sent, so that speech made
at the latter is heard at the former over an
area equal TO that across which the voice
would penetrate in the immediate neighbor.
hood Of the speaker.
The present form Of the instrument by
means of which these marvellous acoustic ef-
fects are produced, consists of very power.
full, compound magnet, formed by the juno
ton Of number of single magnets. This
compound form can be much more strongly
magnetized than one made from a single bar
Of metal, while the process Of magnetizing
adopted in such cases, produces O perma.
nent magnetic effect To the poles of this
are attached coils Of ordinary insulated tel
egraph wire, the spiral arrangement of which
inteusiies electric action. In front Of the
poles thus surrounded, is placed thin sheet,
or diaphram Of iron, and mouth.pisce to
concentrate the sound upon this, substantially
completes the device. 1t has long been
known to scientists that the motion of iron
or steel in front of the poles Of a magnet,
develops, or in technical phrase, induces
electricity in the coils encircling them.
When the human voice or the tones Of an
instrument, set the daphram vibrating, cleo
trio fluctuations are induced in the coils
environiag the magnet, precisely correspond
ing to the atmospheric undulations produced
by the sounds These coils are connected
with the telegraph wire, and along this the
fluctuations are transmitted to the distant
station, where, after passing through the
coils of on instrument precisely similar in
form, they again set this second diaphram
vibrating, which in its turn produces atmos-
pheric fluctuations as audible as those TO
which they owe their origin.
The essential requisites are an exact sim.
DcIWtcu tuC NJ CaCu euu
Of the line, aud the complete insulation of
the connecting wire. The voltaic battery
indispensable to the telegraph, is entirely
dispensed with 10 the telephone, as the cleo.
trio current induced by the apparatus is am.
ply sufficient to convey messages over the
distances hitherto tried. Whether dispatches
can thus be sent to remote points, time and
experiments can alone decide, but there is
every likelihood that the difficulties in this
regard already overcome in telegraphng will
be also obviated in telephoning.
Progress owes this stride in advance to the
ingenuity, thought and labor of Professor A.
Graham Bell who is already honoraby
known in connection with an improved
method of teaching tho deaf and dumb.
Should the promises of usefulness hold out
by his present invention be fulfilled, his name
will long hold an honorable place among the
benefactors Of mankind.