Year: 1877

1uc question WHICH every OHe dsks
relative to the telephone is, how does it
operate? The answer is quite simple if
one will remember that there are two
instruments of the name, has seen the
toy known as the "lover's telegraph"
and is familiar with the operation of
ordinary telegraphic instruments.


Prof. Bells instrument for repeating
the minute shades of tone in converse
ton, dispenses with electricity alto
gether. and uses the wire to convey the
vibrations of sound just as the piece of
string in the "lovers telegraph" AL
though the apparatus at the ends is more
complicated than the little tin cups
covered with parchment, employed in
the toy above mentioned, the principle
is precisely the same. One talks against
sensitive membrane whose delicate
vibrations are impaired to the wire, and
are caught up and rendered audible by
similar membrane on the receiving in
strument miles away. Every one knows
how the sound of an ordinary tuning
fork is made more audible by setting the
small end of the instrument on table.
Just so a sound that could not be heard
along the wire is brought out by the
exquisitely sensitive parchment of the
Bell telephone.


The instrument invented by Professor
Gray is designed to convey exact musi-
cal tones, singly or in chords, and works
on an entirely different plan, and re-
quires through current of electricity,
as in ordinary telegraphing.


The principle upon which the ordin-
ary telegraph depends is that the alter
nate closing and breaking of the electric
current by a key, at the Office of the
sender, magnetizes and demagnetizes
bit of soft iron about which the wire is
coiled at the Office of the receiver; the
changes in the conditions of this bit of
iron causes little lever to bob up and
down, making click by which most
operators read the message, or recording
the intervals of its depressions and
risings by series of dots and dashes on
a slip of slowly moving paper. The
average operator sends thirty words a
minute, averaging five letters word,
and four or five clicks or vibrations to a
letter, or seven hundred and fifty breaks
and reunions OF the electric current
minute. The waves of electricity that
pass over the wire when the Gray tele-
phone is used vary in rate from forty to
five thousand second, but are neverthe-
less perfectly distinct from one another,


and never jumbled.


The sending instrument consists OF
keyboard like a piano, each key strik-
ing and causing to vibrate a tiny bit
of steel called reed, substantially the
same as the reed in a musical instru-
ment. These reeds are of different sizes
and tuned to give out exact tones and
semi-tones, one for each note. 1t is a
well known fact that the difference in
the tone of reed or string in musical
instrument is due to the difference in the
rate of its vibration. The deepest tones
of an organ, for instance, give only forty
vibrations to second, while the shrill-
est note it is possible for the human ear
to hear is made up of five thousand
vibrations to the second. Now the
reeds in telephone are all arranged to
vibrate. when struck by the pianoforte
key, between little magnets in such a


way as to break and restore the through


electric current at each contact, and to


make a contact with every vibration.


As the several notes of piece of music


are played on the keys of the instrument,


the electric fluid goes over the wire in


waves infinitely small but varying in


rate according to the different reeds sue


cessively employed.


At the Office where the music is to be


received, a series of reeds, tuned to
exactly correspond with the first set
are attached to an extremely sensitive
and reverberative sounding board, which


magnifes, so to speak, the faintest vibra


tion of any one of these reeds, and con
verts it into audible sound. This appa
ratus is attached in such a way to the


magnet around which the electric cur


rent flows, that whatever reed CORES
ponds to the peculiar rate of electric


waves in the wire, will vibrate; ano
that vibration, though ininitesimallJ llJ
slight, is made audible by the sounding


board, and lasts just as long as the waves
continue to come at that peculiar rate
The rate of the electric waves is con
stantly changing as different notes art
olr h1,t tba sarlar. Ir,{ hot
: rate, and however brief its continuance


one reed or another on the receivin.
instrument feels its vibration, and re
spends instantaneously. Thus the note
: originally played are reproduced il


exact tone, length and order on the re
ceiving instrument.


1t is just here that one can appreciat
l the value of local battery connection


Force is indestructible but may becom
. minutely attenuated. The electric cul
rent passing over hundreds of miles G
u wire becomes almost imperceptible; bu


if the alternate stops and resumption
which makes the successive waves al


caught by repeater" and made


produce corresponding stops and IT


sumptions in a powerful local curren
Is these latter can be caused to operate th
a telephone instead of the feeble origins
W ones, and the impulse will be made muc
II more perceptible.


l. The apparatus here described is tn
u kind used to reproduce music in Ne
Is York and played in Philadelphi
Is under Strakosch's management.


IL The new interest law of Counecticl
n fixes the rates for future contracts at 81
[e per cent, three hundred and sixty da,
y being counted as a year. Sheuld bo
N rover agree in writing to pay taxes al
t. insurance, the sums actually so pal
st may be legally collected, in addition