Wood County reporter. [volume] (Grand Rapids [i.e. Wisconsin Rapids], Wis.) 1857-1923, 1874-06-25

A TALK ABOUT ELECTRICITY.

/ L..
DO look here. Miss Hortonl Isn't II
curious?" And a group of eager chill.
dren gathered around the desk where their
| teacher was sitting. The kind teacher
LAID down her book and said: "Well,
Eddy, what is it that is so curious?"
Why, | was rubbing this piece of glass
to make it bright, and then when put il
near some pieces OF paper they came
! rlght up to 1t, just as piece of iron does
| to a magnet"
1t must be magnet" said Phoebe
L thought, though, that they were al
ways OF iron, and would attract nothing
else. Isn't It the strangest thing you ever
! saw"
mo-" said the teacher, it is not mag.
net, nor IS 1t any stranger than that the
magnet should attract iron"
linen what makes it draw the paper to
There are many other things besides
magnetism which tend to draw bodies to
each other. In this case it is due to cleo.
But all glass doesn't attract paper; nor
will this, now," said Eddy, vainiy attempt
ing to repeat the experiment.
NO, 1t IS only when rubbed with
wooden, silk, or some such substance that
it will do so. Electricity is of two kinds
| called positive aud negative, which exist
in all bodies, generally in a neutral state
! that is, as much of one kind as another
When piece Of glass is rubbed with a
wooden cloth, the friction separates the
two electricities; the negative going to
the cloth while the positive remains in
the glass. Now, because all bodies have
aitendenCy to become neutral, each kind
attracts the opposite and repels the same
kind; and it is the same with any body
which is charged with electricity Such
bodies will also attract those which are
neutral"
off" said Joseph, call bodies con-
tain electricity, why do they not draw the
paper when rubbed? Iron or wood will
not"
Because these bodies are c0nductors-
that is, they will allow the electricity to
pass through them freely, and as fast rs
the electricity is separated one kind flows
OFT through the hand or whatever it rests
on, while the other kind flows into it,
keeping it neutral all the time. But glass
is nOn-conductor and does not allow the
electricity to escape readily 1t is par
tial conductor, however, and if charged
will return slowly to a neutral state.
This was the case with the piece Eddy
has, when it would not pick up the bits
of paper"
but thought Electricity was fire."
said little Jennie. Father says light
ming is Electricity; and it was lightning
that burnt Mr.. Mead's barn"
"When the tension of electricity is so
great as to cause it to pass through a non
conducting substance it has the appear
ance of sparks; or if the tension is very
great, or the resistance small, it passes
like fame. When at rest, or passing
through a conducting body, it is invisi-
bic. If we were to rub piece of gutta-
percha or sealing-waX it would become
charged with negative electricity. Then
if we should hold it near a piece of glass,
positively charged, the tension would be
so great that the electricity would escape
from one to the other through the air,
which is a non-conductor in the form of
sparks"
81 should think that you might light
fire in that way" said Eddy.
So they could" replied the teacher.
Sufficient heat may be produced by an
electrical current not only to light fires,
but to melt metal and even turn it into
vapor, so that it will pass off into the air
like steam. The most brilliant artificial
lights which can be produced are made
in the same way. In the case of Mr..
Mead's barn, cloud charged, perhaps,
with negative electricity passed over it.
This would draw the positive current to
the surface Of the ground, and when the
tension became great enough the cleo
triCity would escape from the cloud with
a loud report, and striking the barn would
Of course set it on fire. Sometimes it
passes from the earth to the cloud"
But can a spark be drawn from any
thing that is electrified ?" said Joseph
Eyes; and from anything through
which an electric current can be passed.
Wouldn't you think it strange to see any
one touch off gun with piece Of ice ?"
"How funnyn' exclaimed Eddy; while
Phoebe said: Gould one do that? |
should think ice would put out fire."
81 have seen it DONE" said Miss Hor-
ton. THE person who does it stands on
piece of glass and the gun is suspended
by silk cords. These substances are non
conductors, and so do not allow the cleo
tricity to pass through them. Then the
cone of the gun is connected by wire to
the negative pole of a galvanic battery,
an apparatus by which electricity is pro-
duced. The person who shoots the gun
takes hold with one hand of a wire at
tached to the positive pole, and with the
other hand brings piece of ice near the
cone. A spark will then pass between
the ice and the cone which will ignite
the powder and shoot the gun. But as it
is time for school now we cannot talk
any longer this time."-Our F5reSade
Friend.