The Indiana State sentinel. [volume] (Indianapolis) 1868-1895, 1878-12-18
DARKNESS DISPELLED.
An Estimate Of the Cheapness of Edi.
sons Electric Light.
Six Hundred Lights, Each Equal I'm In.
tensity to n Common Gas Jef,
From q Hundred Horse
Power Engine.
New York SUM-

HIS subdivision of the electric light being
perfect and its utility an accomplished fact,
Mr.. Edison has turned his attention toward
a new generating machine. He has already
invented meter for the light which works
to a charm. With the Wallace generating
machine, Mr.. Edison says he can get no
more than three electric Jets, each equal to
one gas jet, from one horse power engine.
Five months ago he began experimenting
with view to saving the loss of electricity
by the Wallace and other machines. The
perfection of his apparatus for subdivision
interrupted these experiments, but now he
is giving almost his sole attention to them.
Two weeks ago he announced that he had
doubled the productive power of the Wal
lace machine. He felt sure that he could
turn out six lights to a one horse power.
With his new so horse power engine he
could force out $50 electric lights in place of
the 240 generated by the Wallace machine.
On Wednesday at 10 a. m. he began a new
series of experiments, believing that he
could still further increase the power of his
own generator The experiments lasted all
night and until 10 a m. OF Thursday. They
were made in the presence of we'll known
New York lawyer, and were successful. More
light was obtained, but exactly how much
more was not asoertained. The inventor
went to bed at IL a. m. thoroughly exhaust
ed and slept until daylight yesterday morn
ing. He visited the city yesterday and re-
turned to Menlo last night.
The announcement that 4S0 electric lights,
equal to common gas lights can be produced
by the use of his proposed generator and an
so horse power engine gives us data by which
we may ascertain the cost of the light with
tolerable degree of accuracy. There are 90
gas burners in the Sun composing room.
They are used, say. IL hours out of the "a.
They cost US last week $54, or $7.71 night,
little over 81 cents apiece. Six hundred
such lights, burned for the same period,
would cost little over $5l per night. At
an over liberal estimate il would take two
tons Of coal to run an engine of 100 horse
power "a hours This would cost 81. The
services of two engineers would cost Sc
more. or S13 in all. For this $13, then, il
Mr.. Edison's statement is correct we could
get 600 lights and burn them "a hours. For
S6 so We could burn them II hours, leaving
the figures thus:
Difference in favor of the latter-..........s 81
Take another estimate. Booths Theater
has 500 gas burners. 1t costs from $50 to
S35 per night to burn them three hours and
half. II Mr.. Edison's estimate is correct,
the managers could burn the same number
of electric lights, of equal brilliancy, twenty
four hours for $32 90, or about $460 for the
three hours snd half. The figures would
stand thus:
l5 gas o
l,5OO electric lights u
Difference In favor of the latter.......s25 A
There are $500 gas burners in A. T.
Stewards retail store. 1t is difficult TO ascer
tain an average of the time they are burned
They cost, however, over $50 per night
| Carrying out the Booths Theater estimate,
Judge Hilton and his partners would save
over $40 night by the use of the electric
lights. tt -t
The Fifth Avenue Hotel has 2,O5O burn
ers. They burn 100000 feet of gas month
in the best times At 81 per thousand this
| would amount to about S34 per night. BY
the use of the electric light they would save
nearly s27 per night, estimating on the
| Booths Theater ratio. ..
All these figures are based on Edison's es-
| timate OF the power of his generator. This
generator has not yet been made. The in
| Yentor bases his assertion on the result OF
his experiments alone. He does, however,
| positively assert that he can get three lights
| per horse power, each equal to gas jet,
| through the use of a Wallace machine. This
| is solid data. The saving per night in the
different buildings above mentioned, the
| conditions being the same, would be as fol.
| lows il Wallace machines were used:
SSun $2 =
Booths " y
A I. 20 0C
Fifth Avenue Hotel......-.- .............. IA p
"Alowing 800 lights to burn II hours.
The above figures are given for what they
| are worth. Edison positively asserts that he
| can get three lights, each equal to common
gas jets, to one horse power by the use OF q
Wallace machine, and more than double
| that number by the use of his proposed gen.
orator. Any school by can ascertain the
cost OF coal and attendance on an engine
nd work tho nrnhlana for hinnsalf A