The Roanoke times. [volume] (Roanoke, Va.) 1890-1895, 1893-05-31
ELECTRICITY ON TAP.
Tho Potent Fluid Now Handled
Like Any Merchandise
Something About the Laws Which Com
troll the movements OF tie Won
dcrful Power - Currents AT
Commercial Rates.


Electricity. once u plaything. then 4
scientific study. is now 4 commercial!
product. Twenty years ago electrical!
energy was generated in the laborn-
tory for experimental purposes by
few physicians as medicine of some.
what questionable rcputc and in weak
currents by those who applied ii to use
in the arts. From the cylinder of glass
or mastic. excited 10y friction to set
cork manilins or pitch balls a-danciig
to the dynamo that runs from one To Il
dozen powerful engines is {. long step.
but one that has been taken within
the memory of men who still call them
selves Young.
Electricity as Il commercial product.
according to the New York Sun. is to
those that deal in it as coinmonpl;
an affair as eggs or butter. The con-
ditioi, and cost of its production are
positively known, and the product NAV
be measured almost as the clerk with
his yardstick measures dry goods. You
may buy your electricity by specific
quantities. and if YOU have the con
venienccs may carry it home with YOU
as you would carry any other purchase.
1t can bc sent to You 10y express or de
hvercd by messenger. or it may be
served out over Il wire in measured
quantity. rs gas and water are served
through pipes. All this seems mystcri-
Gus to those not technically educated.
because the electricity shops do not
count their product 10y dozens or meas
urc it 10y yards and gallons, but use
outlandish determinations and pu2-
- C..in
thcless the shopliccpcrs are at home
with the mysterious timber thing in
which they deal. and they never stop
to think about its mystery, although
just beyond the small field which their
knowledge covers lherc lies an I'M
known area of conjecture.
Electricity as Il commercial product
and handy tool. applicable To anyth
ing that mechanical power can accom-
plish, is thing Approximately of only,
the last ten ycars Before that time
its cost made it mostly matter of
splendid practical possibilities Now.
with conditions given. Skilled cleo
trician can estimate to /; hair the cost
of producing the amount of electricity
necessary to yield a specified power.
IL is chiefly question of the cost OF
coal
The existence Of two simple laws
makes electricity Il practical power for
doing the worlds work. One is hat
when an arinaturc is caused to rotate
within the ia;: ~netic field Il current OF
electricity is excited in the arlnaturc
and may be taken up, carried out over
wire. and returned u the place of
beginning. This is what electricians
call the law of the dynamo. The other
law is that whcna current of clcctrici-
~ is passed through an arnaturc in
closed within the magnetic field the
ar;nature is caused To rotate. That is
what electricians call the law of the
motor. BY the first law a current of
electricity is set up. and by the second
that current is enabled to establish
mechanical motion. When these two
laws became known the problem of
applying electricity TO the worlds
work mainly needed for solution
only cheapening of processes. such as
should make it possible to produce a
current at commercial rates Every
dynamo, whatever its form. as regards
the communication of electric energy,
is essentially an clcctro-lnagnct with a
core of soft iron, the armature inclosed
within The magnetic field, which is the
space between the two poles Of the
electromagnetic. Every motor, what
ever its form, is essentially the same
thing. with the core revolving under
the influence of a current FROM the dy-
namo i'll accordance with the law of
the motor The core of the dynamo,
revolving under the influence of TIL C
magnetic field. is Il shaft, the current
| generated is the belt communicating
| power To another shaft. the core of the
motor. 1t is this transfcrcncc of power
by the invisible belt from the DYNAMO
| to the motor that makes the trolley
cars run, the electrical engine rcvolve.
or any other mechanism perform its
work under the influence of electricity
| thus generated The storage battery
is simply an isolated reservoir of cleo
trical energy, for the time being indie
pendent of the generating source, as if
ii user of water should prefer to fill a
tank III the top of his house once a
week rather than to draw frorl faucets
directly connected with the main
source of supply
Wonders of the Insect World.
EntomoloGists generally concedc
that upward of one hundred thousaa,