th end of the magnet points straight downward, it follows
that it would be more nearly correct to say that, throughout the United
States, the magnetic needle points up and down than that it points
north and south.

Going yet farther north, we find the dip still increasing, until at a
certain point in the arctic regions the north pole of the needle points
downward. In this region the compass is of no use to the traveller or
the navigator. The point is called the Magnetic Pole. Its position has
been located several times by scientific observers. The best
determinations made during the last eighty years agree fairly well in
placing it near 70 degrees north latitude and 97 degrees longitude west
from Greenwich. This point is situated on the west shore of the
Boothian Peninsula, which is bounded on the south end by McClintock
Channel. It is about five hundred miles north of the northwest part of
Hudson Bay. There is a corresponding magnetic pole in the Antarctic
Ocean, or rather on Victoria Land, nearly south of Australia. Its
position has not been so exactly located as in the north, but it is
supposed to be at about 74 degrees of south latitude and 147 degrees of
east longitude from Greenwich.

The magnetic poles used to be looked upon as the points towards which
the respective ends of the needle were attracted. And, as a matter of
fact, the magnetic force is stronger near the poles than elsewhere.
When located in this way by strength of force, it is found that there
is a second north pole in northern Siberia. Its location has not,
however, been so well determined as in the case of the American pole,
and it is not yet satisfactorily shown that there is any one point in
Siberia where the direction of the force is exactly downward.

[Illustration with caption: DIP OF THE MAGNETIC NEEDLE IN VARIOUS
LATITUDES. The arrow points show the direction of the north end of the
magnetic needle, which dips downward in north latitudes, while the
south end dips in south latitudes.]

The declination and dip, taken together, show the exact direction of
the magnetic force at any place. But in order to complete the statement
of the force, one more element must be given--its amount. The intensity
of the magnetic force is determined by suspending a magnet in a
horizontal position, and then allowing it to oscillate back and forth
around the suspension. The stronger the force, the less the time it
will take to oscillate. Thus, by carrying a ma