The San Francisco call., 1899-07-09

Accounts we're published in the press an
80 fba world In short time Ben wa, was
on every tongue and the yqnn6 baY6ond his
-iIdaS+ dreams 1t might be stated Pai,, PSeii
entheticaIly that the Boston press 1Ie nro n
afterward announced the ,la,deT nIanfdL Gra-
Miss Mabel Aupbaru u
iG5n But the the telephone which Bell exhIn1rGidd mnTid
at the Centennianii EEp09th, as the parent Of
The wonderfully complete llsttEaitOib, run tbs
used to-day. 1t is true, however, en1t 1Ub;cT1
basic principles OF the lilsei se,nonI'nting into
now transmit messages anouiilliiiST +ba
the F,Ilions annually are idenqcaiy 1tiis the
same as those first applied py PEI, sb,.c,,,+inT
and of adaptation OF late the prlnclpaI
movements have been erected lT aL9Hs ~ ~
line of long distance telephony uIltIt Cea,
versations can now be carried Oh "e'"
stations 1000 miles apart. e.. ,,,or.
Bell himself discovered that Iad nip1 ~
convenient form Of receiver ran ane was vas
one which substituted circular frou I'VE Tt5S
firmly clasped in front of magnet. - ms ms
was found to vibrate in much Del
unison with the transmitter into w5ic9t
words were spoken at the other emu VI
the circuit. +ri,,-
Although a precisely similar. contr1vr dy,,
ance to the Bell receiver, as II Is nov
generally called, will serve as tLehHo of
mitter as Well an improves E1al,e 9ocar carbon
transmitter has now been generaIiy
adopted. This form of transmittsr 9uD SUI,
StltuteS FOR the magnet DSIiIilu
diaphragm a number of small pieces 5io "a
loose carbon placed between a cdrpoIl @ utoI
phragm and solid support. CARBON Wo1 We
found to be preferable to metaaI on traae-
count of its peculiar properties Tor trans
mitting sound. So delicate ana SuscSpti-
BILE to sound is the carbon transLnltt,eL
that the footballs of a fly crossing tns
carbon disk produce perceptlole souIo
in the telephone.
The carbon transmitter substitutes for
the impulses Of electricity, which WeIe
induced in the original form OF transmIt-
ter by the action of the iron diaphragm
on the magnet, an electric current Whicn
passes directly through the carbon dla-
phragm and the loose carbon behlno ~.
In this case, the vibrations of the voice
falling on the carbon disk affect the cur
rent directly.
The electrical impulses are accentuated
by the motion transmitted through the
disk to the loose carbon. In this shape
they are transmitted to the wire, ana
a. series of impulses corresponding ex-
actIy.in rapidity and shape or quality to
those sent out are then reconverted into
fac-simile sounds at the receiving tnstru-
ment -
battery system, and is in general use at
present on all lines Of any great length.
In the most improved instruments the
Blake carbon transmttter Is used in con-
nection with the Bell receiver.
Specially contrived batteries are now
used for reinforcing the current on long
used to convert the electric vibrations
caused by the voice into suitable form
for long distance transmission; A tnou-
sand improvements in call bells for at
tracing the attention of the central sta
ton, in the arrangement and construction
of the transmitting and receiving, lnstru-
ments themselves, in the system OF switch
boards and switches employed at the cen
trail stations, and in methods OF making
connections, have been added since me
telephone was first put into practlcal
operation by Graham Bell and his asso-
ciates.