Q
341
> (
and in
giving data for determining
the movement
It is
of
the Earth's magnetic pole.
A
precisely at a spot where
the annual change is
small that
a
continuous
series of obserostions
is specially required to determine.
the alteration.
in
the
annual
change year by year.
2.
It is also to be
remarked that if the observations.
ase discontinued for a
years, there
is
a
the
instruments.
disuse and
number of
probability that
will suffer
that when
Comes
for
he com
menting.
from
the time
observations,
they