Omaha daily bee., 1898-07-22

considerably over 100 miles, and moving
objects can be detected by its light almost
as far as marine glasses can carry. II
stands ten feet six inches high to the top
OF the drum, and the total weight Is about
5000 pounds, but so perfectly is II mounted
and balanced that a child can move 1t in
any direction. 1t was built by the General
Electric company OF Schenectady.
The rejecting mirror used is a concave
spherical mirror, five feet in diameter re-
fecting a parallel beam Of light. 1t was
manufactured especially for this protector
and Is a specimen OF perfect optical work.
three and one-fourth inches thick at the
edges and ne-sixteenth of an inch thick
at the center. 1t weighs about 500 pounds.
Inc metal ring In which it is mounted
weighs about $50 pounds, and the total
iens' ring and cover weigh about 1000
pounds. This great mirror is mounted at
one end OF the big drum, the outer end
OF which is furnished with a door con-
sisting OF a number OF plate glass strips.
inside the drum and sliding Upon ways ar
ranged on the bottom is placed the electric
arc lamp, the source of the light which is
reflected by the mirror. 1t Is entirely auto
matte In its action, Is six feet high and
weighs about 400 pounds. The carbons
used are also made especially for 1t. The
upper or positive carbon is one and one
half inches in diameter and twenty-five and
one-half Inches long. The lower or mega
tive carbon is one and one-fourth inches
In diameter and fifteen inches long. The
outer surfaces of the carbons are heavily
coated with copper. The positive carbon is
set n little in front Of the negative and
thus almost all the iptapgo l;nba - A.
incandescent crater of the arc is cast upon
the reflector.
Progress of Electric Power.
Before the days of the steam engine, that
Is to say In its present form, the city which
enjoyed the advantage of water power be-
came almost certainly a manufacturing city.
Later on. when coal became cheaper by
reason OF better transportation facilities,
the steam engine largely took the place Of
the water wheel. Now that by modern
electrical machinery energy can be so easily
transformed into heat and light, and power
can be transmitted over wires, the city by
the waterfall may regain it's former pres
tige. 1t is a comforting thought, observes
the Baltimore Sun, that the people Of a
town can get from the fast flowing river
not only power to operate machines, but
light for their homes and streets and heat
to warm their dwellings and cook their
meals. In California, where fuel Is scarce
and expensive, much attention is paid at
this time to utilizing the energy OF streams
by means Of electric machinery. 1t Red
lands, California, there is an electric plant
which delivers the power of a waterfall
at a distance of twenty miles. At Fresno
the power is carried thirty-fve miles. Here
is an enormous water power, and the en-
-.-. --.,-- -,,z. L ..-- L. q nm l~-n
power. The time may come when sun
energy may be preserved in storage bat
teries and the power of the winds and tides
be utilized in the same manner.
I"ncandescent Lamp Generates Heat
The incandescent electric lamp, says the
London Lancet, is essentially a device
which transforms electricity partly into
light, but mostly into heat. AS Is well
known, the carbon filament Of the lamp is
a substance offering great resistance to the
passage Of the current, and the product Of
this resistance is light and heat. 1t is an
instance Of the translation of one form OF
energy into another. 1t may not, however,
generally be known that the light produced
is but after all only a small percentage of
the energy thus manifested-some 5 or 6
per cent only at the most. This fact is
important, bearing in mind a common no
ton that the electric incandescent lamp
Is free from heat rays. 1t is true that the
lamp when working is not comparable with
a dame or naked light, but at the same
time the heat evolved is such as may lead
to ignition. We are disposed to emphasize
this point because the incandescent electric
lamp is used for the purposes OF llumina
ton and decoration in shops without any
regard to the possibility, nay, probability
of fancy goods being fired which happen
to be contiguous. Indeed, so firm is the
idea that the incandescent electric lamp is
free from heat that 1t is frequently to be
found buried in a mass OF easily 1gnlteo
and highly infammable material. This IL
a mistake. and care should be exercised
with the electric lamp in its application In
his connection, but the risk, Of course
is not so great as where naked lights are
employed. We have found by experiment
that on immersing a 16-candle power LAM
400 volts pressure) in half a pint of watel
the water boils within an hour and il
proportionately less time when q 32-candlt
power lamp is substituted. II again thu
lamp be buried in cotton wool, the WOO
soon begins to scorch and ultimately Il
r burst into flame; in one experiment which
we tried the bursting into flame of thu
wool was accompanied by a loud report
, due to the explosion of the lamp. 1t clearl!
appears from this that the incandescen
electric lamp cannot be regarded as an un'
likely means of starting a serious fire, anC
( shopkeepers, especially those who exhibi
l highly inflammable fabrics, should know
1 that there is a risk in placing such good
r too close to the lamp. The lamp in con
r tact with celluloid fires it in less than hv
r minutes, and therefore the danger is par
g, t4,,I 4 rtN -. Il. Ia naBA ~ t1,y -
Q where incandescent electric lamps are Otter
suspended in the midst of toy ~celluloit
s balls.
. TAKES A SHOT AT STRIKERS