The times. [volume] (Washington [D.C.]) 1897-1901, 1901-02-10


wire are in most cases wound separately
| and then placed in the spaces between the
projections. constituting. in fact, form
of drum winding. In the early 1Os few
Gramme ring and Siemens drum machines
had been applied to the running of arc
lights, one machine for each Hight There
We're also some Gramme machines in use
for electropating.
At the Centennial Exhibition, held at
Philadelphia in 1876, but two exhibits OF
electric lighting apparatus were to be
found. OF these one was the Gramme and
the other the Wallace-Farmer exhibit
The Wallace-Farmer dynamo machine is
type now obsolete 1t was not good de-
sign, but the Wallace exhibit contained
other examples rejecting great credit on
this American pioneer in dynamo work.
Some of these machines were very similar
in construction to later forms which went
into very extensive use The large search
lights occasionally used in night illumina-
ton during the exhibitions were operated
by the current from Wallace-Farmer ma
chimes The Gramme exhibit was re-
markable exhibit for its time. Though
not extensive 1t was most instructive.
There were found in II dynamo running
an arc lamp: large machine for electro
lytic work such as electropiating or cleo
trOtyping, and. most novel and interesting
of all, one Gramme machine driven by
power was connected to another by pair
of wires and the second ran as
motor. This in turn drove n centrifugal
pump. and raised water which flowed in n
small fall or cataract. year or TWO
previously the Gramme machine had been
accidentally found to be as excellent an
electric motor as It was a generating dy-
namo. The crude motors of Jacob. Fro
ment. Davenport. Page, Vergnes, Gaume.
and many others were thus rendered OBJ
solete at a stroke. The first public dem
onstration of the working of one Gramme
machine by another was made by Fon-
tame at the Vienna Exhibition of 1873
Here, then. was foreshadowing of the
great electric power transmission plants
of today; the suggestion of the electric
station furnishing power as well as light,
and to 4 less degree the promise Of future
railways using electric power. Replace the
centrifugal pump of this modest exhibit
by turbine wheel, reverse the flow OF
water so az to cause II to drive the cleo
trio motor so that the machine becomes
dynamo, and in like manner make of the
dynamo motor, and we exemplify in
simple way recent great enterprises using
water power for the generation of current
to be transmitted over lines to distant
electric motors or lights.
The Centennial Exhibition also marks
the beginning, the very birth, 1t may be
Et1,, IN
become. before the close of the century.
most potent factor in human affairs. The
speaking telephone of Alexander Graham
Bell was there exhibited for the first time
to the savants, among whom was the dis
tinguished electrician and scientist Sir
William Thomson. For the first time in
the history of the world a structure of
copper wire and iron spoke to a listening
ear. Nay, more. Ii both listened to the
voice of the speaker and repeated the
voice at a far distant point. The instru-
ments were, moreover. the acme Of sim
pIicity Within year many boy had
constructed a pair of telephones at an
expenditure for material Of only a few
pennies In it's first form the transmit
ting telephone was the counterpart of the
ton The transmitter was in reality
minute dynamo driven by the aerial voice
waves: the receiver, Vibratory motor
worked by the vibratory currents from
the transmitter and reproducing the aerial
motions. This arrangement, most beauti-
full in theory. was only suited for use on
short lines, and was soon afterward re-
placed by various forms OF carbon micro
phone transmitter. to the production of
which many inventors had turned their
attention, notably Edison. Hughes. Blake.
and Hunnings, In modern transmltterS
the voice wave does not furnish the pow
er to generator the telephone current. but
ONLY controls the flow of an already ex-
listing current from a battery. In this
way the effects obtainable may be made
sufficiently powerful for transmission to
listeners 1.50o miles away.
There Is no need to dwell here upon the
enormous saving of time secured by the
telephone and the profound effect its In
PRODUCTION has had upon business and So
cial life. The situation Is too palpable.
Nevertheless, few users Of this wonderful
invention realize how much thought and
skill have been employed in working out
the details of exchange switchboards, of
signaling devices, of underground cables.
and overhead wires, and of the speaking
instruments themselves Few of those who
talk between Boston and Chicago know
that in doing so they have for the exclu-
sive use of their voices a total of over
!. 900 900 pounds OF copper wire in the
single line There probably now exists in
the United States alone between 1900
ard 10000 miles off hard drawn copper
wire for long-distance telephone service.
and over I50.co0 miles of wire in under
ground conduts There are upward of
three-ouarters of d million telephones in
the United States, and including both
overhead and underground lines total OF
more than half million miles of wire.
Approximately one thousand million con>
yeraations are annually conveyed.
The possibility of sub-oceanic telephone
ing is frequently discussed, but the prob
lem thus far is not solved. 1t involves
grave difficulties, and We may hope that
its solution is to be one of the advances
which will mark the coming century's
progress.
The advent Of the telephone in 1876
seemed to stimulate invention in the cleo
tric field to a remarkable degree. Its i'm
| mediate commercial success probably
acted also to inspire confidence in other
proposed electric enterprises Greater at
tention than ever before began TO be given
10 the problem of electric lighting. An
electric arc lamp. probably the only one
In regular use, had been installed at Dun
| eeness lighthouse in 1867, after a long set
of trials and tests. 1t was fed by Holmes