National Republican. (Washington City (D.C.)) 1872-1888, 1886-04-17


the surrounding insulated coils. These
their location by bringing any magnenc
sSey poles Ss Of Pe eG 9ar od f Now n tSe
diaphragms constitute in both instances
such magnetic substances. II they are
entirely removed the imaginary lines extend
out nearly at right angles TO the axes Of the
magnets, and when TREY are replaced these
lines are drawn In the direction Of the dia-
phragms, and for intermediate distances
they assume intermediate positions, sweep
ing back and forth over the surrounding
coils Of wire. Thus IL will be seen that, ON
causing the transmitting diaphragm to APP
proaoh the pole OF Its magnet, the magnetic
lines OF force are drawn toward II, and they
swing bodily across the wire OF the sur
rounding coll; but such an action, 1t will
be remembered from what we have above
said, generates O current Of electricity In
the coil, and hence throughout the entire
circuit. Hence 1t increases the magnetism
In the coil Of the receiver, thereby creating
increasedlin Of magnetic force In the core
and causingits diaphragm to be attracted In
direct proportion to the current generated.
| Now, under action OF the voice, the trans
| hitting diaphragm must assume many
| positions, and, as the sound waves vary In
their intensity, their pitch, and quality,
| they must create set Of forces which cause
II
imaginable positions, from Its neutral or
| silent positions to it's point Of widest ex-
cursion. IL must at times pass forward on
| its excursion with one velocity, react under
another, and again advance under still an
other velocity, ultimately reaching Its ex-
IRENE dead point, or point OF widest ex-
cursion, thereby causing the lines Of mag
| netic force to impress upon the surround
ing coil their effect In electrical waves,
| which are exactly similar In form to the
sound waves uttered. These electrical
waves are forced through the connecting
conductor, and tend, as We have indicated,
to electrically control orregulate the action
Of the receiving diaphragm.
1t will be understood that the transmit
ting diaphragm acts under three forces,
viz: First. the power. OF the voice; second,
the core, and that the receiving diaphragm
acts also under three forces, as follows;
First, It's elasticity; second, the varying
attraction OF the core and coil; third, the
permanent attraction or repulsion OF the
| core.
In order to copy accurately the tones
transmitted, this diaphragm should be
always under the control OF the transmit
ting current during the act OF transmitting.
In other words, the elastic power residing
In the diaphragm should never be allowed
/
diaphragm at any part of its excursion,
save, perhaps, at the dead point or point OF
extreme amplitude, and then, as Is neces-
sarily the case, only for the very smallest
traction Of a second. II this electric energy
is removed from the line during an inter
mediate part Of the excursion, the dla-
pbragm gives of at once its own peculiar
metallic tone, just as a tuning fork will do
when released by the finger. II Ia by virtue
of this resultant force existing between the
elasticity Of the diaphragm and the con
Meeting link Of current variations on the
line Nhat 1t is made to copy exactly the
tone quality OF the voice. Any one who
has used pair of magnetic telephones
must have noticed how much more clearly
they talk than do existing contact tele'
phones.
1t will be understood that as the trans
hitting diaphragm advances from It's neu'
trial or stationary point 1t generates 9
current Of electricity In one direction and
that as II recedes IL reverses the direction
OF the current and hence tends to cause the
receiving diaphragm to be repealed, boil
dlaphragms going through the same phases
in their respective excursions.
There are many delicate phenomena
such as self-induction, magnetic slugglsh
ness. &C., which enter into the problem
but 1t Is not necessary to discuss here, tn
essential features Of speech transmission
having been portrayed. Such is the actio
Of this simple and effective instrument, q
once the most useful and wonderful inyeu
ton OF the century.
We have not space here to discuss II
later outgrowth, the contact telephon
now In general use, but will devote GU
next article to 1t, and give ageneral insigh
into the advance made In more modeI
telephones, having especial reference to 81
called long distance and loud speakiu
! telephones, together with general reyie
the telephone field, as now disclosed |
| ! he records OF the patent office,