The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1893-10-15
a DREAM COME TRUE.
Amazing Advance in Electricity
Since the Centennial Exhibition.

Prof. A G. Dolbear. in Cosmopolitan.
How rapid the development of the cleo
trical arts has been within the past Few
years may be seen by comparing the cleo
trical exhibits at the Centennial exhibition.
in Philadelphia, in 1876, with those at the
Columbian exposition now at Chicago.
Then, electrical apparatus consisted mostly
of telegraphic devices, galvanic batteries,
static machines Leyden jars, etc., for
school illustrations and measuring instru-
ments, such as galvanometers and resist
ance coils. There were a few crude dyna-
mos and one small imported Gramme ma
chine, none of them intended to maintain
more than one arc light. Now, there is
rivalry for space in which to exhibit dyna-
mos capable of lighting fifty or more in one
circuit. Then there was not single incan-
descent lamp in the world. Now they are
to be seen by the tens of thousands, and
with all degrees of brightness. from that of
a tallow dip TO those but little inferior
to the arc itself, and every exhibit is thus
lighted. Then there was not single cleo
trical motor that was more than a toy to
be run by galvanic cell. Now. motors for
all Kinds of service, from driving a fan to
those running printing presses. looms. na-
chine shops and threatening the existence
of the locomotive itself.
Ihen all welding was done by hammer
ing at the forge. Now, electricity heats
the ends to be joined and in less time than
II takes to describe. the process, heavy
than was possible before. Then, ii was not
possible to weld steel or other metals than
IRON NOW, almost any metal may be cleo
tr1cally welded to another as easily iron
to iron. Then, there were induction coils
Tor producing sparks a few inches long.
Now, such sparks have been made five feet
long, and, 1t is believed, could be made
nifty feet long If ii were worth the while.
Then, induction coils were employed only
for changing low potentials TO higher.
Now, the transformer reverses the process
and makes electric lighting feasible miles
away from the dynamo. Then, ii was pos
slble to send but two telegraphic messag es
IN opposite directions simultaneously. Now,
seVenty-tWo messages can be sent, thirty
SIX in each direction, one wire without
interference. Then, the telephone first
exhibited on a line the length OF building.
Now, one can talk with another a thousand
miles away. =, fs|
Then, it was believed that continuous
conductor was essential for doing any kind
OF electrical work. Now, 1t is shown that
all kinds of such work may be done with
out material connections. Then. il was
thought that light was one of the physical
forces. Now, it is believed that light is
an electromagnetic wave. Then, it was
believed and taught that electricity could
never be economically employed for driv-
Ing machinery, and that its light could not
be subdivided. Now, IL is believed that cleo
tricity is in its infancy. Then, all the
electrical exhibit could be put in a space
fifty feet square. Now, a huge building,
covering acres, is found to be insufficient
for the needs of the exhibitors. All this
since 1876.