National Republican. (Washington City (D.C.)) 1872-1888, 1886-01-02
ELECTRIC SCIENCE.

hintncr, IrinClphl Nhaininefi NihHs OF
Electricity, United States Patent once.
Light, says Clarl, Maxwell, is q strain or
force getting through medium OF trans
mission, and that medium, IL VIC refer to
sunlight, is the ether in space through
which II transmits this strain from the sun
TO the eye. There is no wide difference
In principle between the light emitted from
candle a gas jet, the sun, or an electric
lamp. Each kind Of light, like sound aud
heat, is the result Of rapid vibrations or UNI
dulations impaired to the elements OF the
medium through which Il reaches the eye.
We light tallow candle with q friction
match, which, in turn, is lighted by heat
due TO the vibrations impaired TO It's
molecules by friction. In the candle,
when once lighted, the action is purely
chemical, In fact is nothing more
nor less than n process Of oxidation exist
ing between the oxygen of the atmosphere
and the combustible carbon Of the tnllOw;
this oxidation evolves heat, and the heat IN
turn Is sufficient TO set up rapid molecular
vibrations In the air which affect the Opti-
cal nerve In the nature of sensation
known as light, just as sound affects the
auditory nerve by undulatory vibrations of
air set up by u vbratory body. In the gas
Jet the process Is much the same, the ONida-
tion taking place between the element of
carbon found In IL and the oxygen Of the
atmosphere as before. With sun light the
phenomenon Is probably electrical rather
than chemical, innsmuch as It and the cleo
trio light are almost identical in their
nature fact made known by the spec
trun, which gives almost the same analysis
for both.
In the electric arc light the process is, in
measure, similar, or at least bears gen
eral resemblance, tp that OF the candle or
the gas Jet inasmuch as there Is some com
bustiOn, while In the incnndescent light
there is a radical difference, no combustion
taking place at ALL Before discussing this
matter further we will first note the fact
that the patent office recognizes three
classes In the art Of electric lighting, as fol-
lows: /. Electric lighting; lights arc. 9.
Electric lights lights, incandescent. 3.
Electric lighting; lights, systems, and appli-
ances.
BY arc lights Is meant all electric lights
formed by the action Of electricity 1T the
junction Of two electrodes 40 that they
waste away 10y combustion. This includes
also what we sometimes dcnominnte semi
incandescert lights, or those which burn
only by incnndescence or glow at tho
function OF two electrodes without actual
separation, and hence without an arc, such,
for instance, as the Wardermann.
By ircandescent lights we mean all cleo
trio lights which burn by virtue of the glow
due TO the heat generated by an electric
current In continuous conductor or fla
mcut as in the Edison, the Weston, the
Maxim, &c.
BY systems aud appliances We mean all
apparatus involved In and necessary to the
complete electric light plant; such ms reg
ulators, fixtures, fusible cut-outs, switches,
complete systems Of wiring, involving pro-
portions, &c.
Electricity, as we have heretofore indl-
Gated, is simply an imponderublc agent
known only by its results.
II is in short not matter, but Is property
Of matter and its peculiaritles are more
notably visible In the electric light than
elsewhere. II a current Of electricity be
passed through conductor 1t will gencr-
ate beat In 1t according to Il known law.
' Now we know that a given amount Of
heat will develop known amount of light:
remembering that all light Is the result Of
heat II is easy 20 arrive by this formula at a
definite conclusion as to the amount OF heat,
and hence light, given generator will de-
velop. and under varying conditions. II Is
also known that n given amount OF heat
has its exact equivalent In work of energy.
In other words that 10 takes certain
amount Of work or energy to develop
specified amount Of heat.
Knowing these facts we can readily com
putc what amount Of horsepower or energy
Is required to develop a specified amount
Of heat and hence also Of light, OF course
the computations are quite complicated, as
they involve many elements such as the
quantity and quality Of coal to be burned
under the boiler, the character of the steam
engine, the loss by friction Of parts, the
character of the dynamo, including its re-
sistance, &c, the resistance Of the outlying
circuit including each lamp and the pecu-
IL, 80, tl,, 1.ai Ito, ,g,C
current, sc.
As carly as 1850 Sir Humphry Davy dis
covered that II two carbon pencils or cleo
trodes he Joined end to end In an electric
circuit, with battery of sufficient electro
motive force or pressure, say ilfty Bunsen
cells, and then the pencils be gradually
separated, brilliant light would result In
the shape OF a curve or arc between them
until the points OF the pencils had burned
away too far to allow the current to pass
The arc thus formed is the result Of the
high resistance offered to the current of
electricity at the ends OF the carbons, and
is caused by the glow or incandescencc of Il
stream Of carbon vapOr flowing between the
carbon points with the current OF electric
ity. This was the origin Of the electric
light. Ii took its name from the brilliant
curved arc always seen between the cartoons
of an arc lamp when they are separated
sufficient distance. Sir Humphry, elated
ut his discovery, supposed he had found
new method Of artificial lighting,
destined to revolutionize the art OF illumi-
nation. Little did he imagine that 1t
would be over three-quarters OF century
before this form Of light would be made
available.
Two things prevented his success, viz,
a proper regulator TO keep the carbon points
always at the same distance, and an eco
nomical generator to furnish the current at
reasonable cost. In our article upon bat
teries 1t will be rememberedwe spoke Of the
wonderful amount OF energy which has
been exercised by inventors TO produce
battery for this purpose, and yet without
avail.
Early in this century a perfect arc-light
regulator was developed for feeding the
caIbons, and as early as 1896 Messrs. Static,
Du BOsq, Sellon, Browning, and Others had
invented and patented in England arc lamps
complete in every detail, and one of which,
for use where only one lamp is required in
a circuit, is perhaps as good as can be found
to-day. To serve It's purpose well an arc
light should feed the carbOns steadily and
with such regularity as to prevent ilickerlng
or jumping Of the light.
One of the earliest forms Of the arc lamp,
and one Of tho hest, the Sellon, is com
posed OF the framework sustaining sprlng-
impelled-clock mechanism for advancing
and retracting the carbons attached TO rack
bars actuated by the clock mechanism.
This mechanism is controlled by an electro
magnet In the direct circuit with the carbon
pencils, the armature Of which acts as
detent TO stop aud release the mechanism
80 as 10 allow the Carbons to be held or adj
vanced as the current becomes stronger or
weaker by virtue Of their approach or sep.
aration. 1t will be understood that Saveral
OF these lights can be operated on a single
circuit for the reason that when the carbOns
Of any one lamp become widely separated
the magnets will feed the carbons In all the
lamps at once, and thus soon feed them all
together, except one pair, which will con
tinue to burn after the others have gone
out, The desirabilitY to thus arrange lamps
in series or tandem In single circuit for