The Indianapolis journal., 1888-01-15
HOW ELECTRIC LIGHTS ARE MADE.
The Strange Process by Which the Great Mod
ern Illuminating Machinery Is Produced.


The manufacture of electric-light s'plants." or
the machinery and apparatus to produce and
distribute electric light, is the latest evolution
of science and inventive genius. and one of the
largest establishments employed in that work
is in Indanapolis or rather its West Side sub
urb. It's existence is an attestation of the ad-
vantages of this point site for industrial es-
tablishments producing articles for general dis
tribution, and the facilities for the distribution
that supports such enterprises.
Much of the work in the construction of an
electrc-lght apparatus Is not greatly differ
ent from other work in metals. The
combinations produce vastly different re-
rults. to be sure, but the casting, and
hammering, and filing, and drilling go on alike IN
making dynamo or a ROLLER mill" The curl
features are not many. but they are so
wholly different from any other work IN mill or
factory that a short account of them may not be
without In terest to good many readers. Ihere
were three particularly noted oy oournal re-
porter who recently accompanied the secretary,
Mr.. Rorison, through the works at the south
end of the Nordyke d Marmon mlllwork
Here 175 hands are employed, and more are
needed. Plants have been sent to nine cities In
California and four in Texas. making IN all
twenty carloads of twenty tons each. or near 1T,
and orders constantly ahead of their ability
TO meet them. the three especially attractive
features noted were, first, the testing or the arc
lights; second, making vacuums IN the little
glass globes for ipcandescent lights, and third,
testing the completeness of the vacuum and the
consequent efficiency or failure of the light.
In testing the arc light a number OF the open
globe lamps. with automatically regulated car
bons, are hung up together in the test room and
connected with a wire running to a dynamo In
the workshop below, which operates all the arc
lights of West Indianapolis. The intensity OF
the light of each is there examined. and the eff
fciency of the apparatus moving thea carbons.
The arc light is usually equal to 1000 candles,
but this intensity can be doubled by drawing
the carbons slightly further apart When so
close together seemingly to touch, the light
is intensely bright, white spot. without gilt
ter or rays and without any painful effect on
the eyes. A hairs breath of greater separation
shoots out dazzling brilliance that the
eye cannot bear when the ground glass globe is
removed. Another hairs breadth of separation
makes miniature sun with binding rays dart
ing out in a Thousand directions, and filling the
air all about with binding scintillations that
might for intensity be scales knocked from the
sun by one of the comets that some philosophers
believe make solar heat and light by their col
lision. Yet all this amazing light eQualing
1000 to 4, 900. 5000 candles, is produced by
spark not larger, apparently, than the burning
coal on the end of a match, rising from the bub-
bling surface OF the lower carbon, which the in
tense heat fuses, scoops into minute hollows
and keeps necessarily boiling. like a micro
scopic eruption of an ininitesimal volcano.
Nothing of this be discerned through the
ground glass globe that commonly covers the
arc light
The incandescent light for domestic in
dustrial use must be produced in vacuum A
perfect one is, of course impossible. Not be-
cause mature abhors vacuum, as the old
schollasts and alchenistS asserted, but because
human ingenuity has not hit upon any plan to
make it. But practically compiete one 1s
made for the electric incandescent light, as 1t is
made in the mercurial Thermometer, "the
Torrecillian," as it is called Both sides of a
small room set as high as the face of an
average man with cases to which are dt attached he'd
alternating with the elongated little globes of
the electric light and all are connected by
pipes controlled by stop-cocks. The larger
globes, holding a quart apparently. are filled
with mercury, which can be passed from them
TO the light globes, whence the metal expels the
air as 1t fills them Glass tubes in the necks
of the little pecan-shaped globes show the air
bubbles passing up through the mercury there,
and the manager of this departments says it
takes about five hours to make sure of as COM |
to the agencies far devised. When the |
vacuum is completed the little globe is hermeti
cally closed, and is ready for the test
The electric current enters the lncandescent |
globe through two minute fi1aments hardly |
larger than hair, little less than an inch |
long, standing parallel. and half inch or
more apart These flaments are, the inventor |
says. nearly pure carbon. short of diamond !
making, as chemical skill and mechanical inge- |
nuity get at it. The globes, exhausted of |
air and ready for testing. are hung on little cross
arms revolving on the tops of slender sup |
ports high a mans head through |
which the electric, current is passed. |
row of half dozen moro of |
these surmounts the vacuum apparatus on each
side of the room. The first appearance of the |
current in the globe is a faint hair line of red |
light, in the form of an elongated horseshoe,
barely perceptibie to the keenest inspection.
Then the red deepens and widens, and puts off
purple violet tint that seems to accompany
the first show of light. Next the red lightens to
a whittier color, and the horseshoe grows still |
broader and brighter Finally it's light is pure
white, steady and brilliant. but not dazzling.
Then the test is complete and the globe is ready
for use About two Thousand pounds of mercu-
~ required for evacuatine one full set of ir-
globes, and, there is no consump-
ton and very little waste in this of it, the
amount required for one days work will serve
'or every day of the year. and a dozen years.
Starting a Criminal Career.