The Portland daily press., 1894-12-21
MYSTERIOUS FORCES.
Professor Chapman's Interesting Lecture
and experimental Beard of Iron
Strength of a Magnet,

The lecture of Professor W. H. Chap
man, at the rooms of the Y. NJ. G. A..
Thursday evening, was very interesting
discussion OF electrical theories and phe-
nomena. Professor Chapman began
with the magnet. He said that the &C.
ton of the magnet in drawing piece of
metal to itself showed that there was
some agency between the two, upon
which.the magnetism could act. When a
horse draws wagon, we know that
there must, be some medium, like sthe
traces, which enables force to be COM
municated from the animal to the vehi-
vehicle So there must be some medium
on which the lines of force operate from
the magnet to the metal. The medium
by which sound is..transmitted is air, for
sound does not cross vacuum. Sunlight
is TRANSMITTED through something which
we call luminiferous ether. So there is
something through which the lines of
force from the magnet travel and oper-
ate.
Professor Chapman gave some interest
ing experiments to show the action of
these lines of force, which travel in
curves By placing iron filings on sheet
of paper, under which was magnet,
the filings were seen to arrange them
selves in curved lines, which started
out from one pole of the magnet, and
after making circles of greater or less
length, return to the other pole.
Electricity and magnetism are as in
timately connected as two links of a
ting an iron within coil of live" wire,
that iron would become magnetized, the
wire creating around the iron the lines
of force pertaining to magnetism. An
interesting experiment was performed by
taking U shaped magnet, with coil
OF live" wire hung within it. This
magnet was hung to horizontal bar by
it's force of attraction, and Professor
Chapman suspended his whole weight
from this magnet without detaching it,
The minute the current of electricity in
the coil of wire was stopped, the magnet
fell of it's own weight.
In showing that the lines of magnetic
force travel through articles like paper,
wood, or the human body, the lecturer
performed one particularly interesting
experiment. Putting piece of iron III
his closed mouth, he placed around his
head a coil of live" wire. This made
the iron in his mouth magnetic. To
show that his body was no hindrance TO
the operation of the lines of force of the
magnet in his mouth, he hung from his
Inns several iron screws, and from his
chin an iron chain. Magnetic force is
nat known to have any effect on the hui
man body. The same is not true OF cleo
tricaI force however.
Speaking OF the mysterious force, the
lecturer said that it was generally sup
nosed thai it could be observed only
throueh mechanical devices, but he
knew of a rnan-wonderfuuy constituted
bysicalIy-who cali tell the positive
from the negative pole by touch.
One of the curious things about the
magnetic flow is that it is maintained in
iron only short time after 1T has been
induced, while in hard steel the magnet
ic force once induced continues for
years. An alternating current OF elec-
tricity will. however, break up the mag
netlsm in steel.
Electricity and magnetism are not
generated or manufactured. Every
thing is full.of them. All our dynamos
do is to set them loose. A current OF
magnetism sets electricity circulating.
and.vice versa. Electricity is a movements
of the 1mponderable ether in one direct
ion; while magnetism is its movement
in the opposite direction.
Professor Chapman is connected with
the Belknap Motor Company in this
city.