Evening star. [volume] (Washington, D.C.) 1854-1972, 1910-07-28
MAGNETIC POLES
In a Constant State of Motion
Along a Spiral Curve.
EARTH'S MAGNETIC PHASES
Suns Vertical Rays Form an Elec-
trical Helix.
COMPASS DIP AND SWING
II ALI Factors Were Equal Would
Indicate Position of an
Observer.
EARTH'S MAGNETIC PHASES
COMPASS DIP AND SWING
By Edwin Fairfax Naulty.

By Edwin Fairfax Naulty.
Defamation and variation are. or rather
have BEEN the two great mysteries of
magnetism. Defamation is the dip of the
magnetic needle below the plane of OBJ
sSvation; variation is the swing of the
magnetic needle east or west of the
meridian. In addition TO these two there
are other perturbations of freely sus
pended magnetized needle or bar, the
most important of which is deviation.
Deviation is due to local causes, while
deciination or dip and variation or swing,
are due to remote causes. Into these re-
mote causes we will examine and see il
we can find a satisfactory explanation
for them
If the geographical and magnetic poles
conceded and if magnetic eXertion were
evenly disposed over the earth, or through
it, or around it, the compass needle would
dip one degree for each degree of in
creasing latitude north or south of the
equator; there would be no variation. or
swing to the east or west, and the mar
iner'S compass would indicate latitude
with precision, since scale could be ar
ranged to show by the degrees of declina-
ton the latitude of the place of observa-
ton. But the magnetic and geographical
poles do not now agree.
ROAD Amundsen, the Morse explorer,
who made the lower arctic passage and
sailed around the North American conu-
nent; Chetwynd, the famous English mag
netician: Littlehales. the equally aDie
American, and the charts issued by the
American, British. French and German
governments do not agree about the pre-
else location of the north magnetic pole
An average of the views places lt at about
93 west longitude and about - degrees
ncrth latitude and gives it location IN
Boothia, an island or peninsula In the
arctic, IS degrees from the north seo-
graphic pole. In neither the chart OF the
.'yarjation of the compass for 1910 or the
bydrographic office nor in the chart OF
the secular change in the direction OF
the magnetic needle. or In LittiehaIes
splendid Contributions to Ierrestr!ai
Magnetism" is the precise point or 10
cation of the north magnetic pole shown
Chetwynd lacking the scientihc cau'lon
of I.ittlehales, boldly shows 1t as at "
degrees west and - degrees north. O1
none of the four charts issued WIN Loi .
Kelyin's compass guide is the magnetic
pole indicated precisely. But In all %
these admirable charts an area or mag
netic verticity, or polar area, is SHOWN
Variations Observed.
Amundsen last summer told me that ne
had observed certain movements OF the
compa sses he used that he could not eX-
plain, and in April this year ShacKletoh
told me that DIR. Mawson, in charge vi
his south magnetic party, had observed
an area in the Antarctic or fourteen
miles radius, or twenty-eight miles d.
ameter. in which the magnetic needie
was vertical
The perturbations of the magnetic nee
die daily monthly, annual, periodical ana
epochal in declination. variation aho
translation, agree with axial and ornitai
movements of the solar system-tne sun,
the moon the earth, the other pianets
and the hemisphere of sunlight In the
earth's atmosphere
II We extend the ecliptic or plane OF the
orbital path of the earth around the sun
and assume that 1t divides our solar sys-
tenn into two hemisplHpes we md tnat
the axis of the sun is inclined TO TINS
plane : degrees and 20 minutes, tne axis III,
Of the earth is inclined to this plane %
degrees "a minutes IA seconds. the axis
OF the moon is inclined to this plane
degree 80 minutes SECONDS.
FOR the purposes of this article we
need not consider the inclination or the
axes of the planets, since the mashe,ie
enact of the planets is small and the
major demonstrations VIII inciuoe 'he
minor ones by implication
The magnetic equator is glrdle OF the
earth. partly north and partly south OF
The peoeraphical equator, on which the
north and south seeking ends OF mag
netized bar are equally acted on by mag
netic pressure. IL we begin at bah1a, III
Brazil. we will find the masnenc eauA .t
to sweep sharply northwest across 'ne
soutb Atlantic to a little north or cape
Palmas on the west coast OF Africa
Thence it sweeps across AFRICA 10 Sape
Guardifui; thence across the inoian OCEAN
10 Cape Camorin. where IT begins 10 Drop
toward the geographical equator II con-
tinues i'm a soft curve across the fhlIp-
pjnes crosses the geographical equdtol
little east of the 1SDth meridian, SWEEPS
at,tr a
south America north of Callao, and from
there makes an arc across South America
TO Bahia. 49,.
II is this last arc to the southwark that
gives us one key, for this indicates an
attempt to describe an ellipticaf curve on
a sphere as il the greater energy exerted
on the earth by the sun AZ perrneHoiI
were thus mysteriously charteo. inns IL
the magnetic equator as 1t Is charteo.
Tb. chartjne is not quite correct, since
/, ia compiied from data obtained on dli,
rerent dates. and il should De conplleu
from data taken simultaneously a'ohs
tho line in at least one day.
=, yo,, take a rod of steel and place it
inside a spiral coil of copper wire and
then pass a current OF electrihcatioh
through the copper wire you VIII magnet
i've the steel rod If this is done away
from other magnetizing influences you
will get a simple magnetic state In the
steel rod depending on the kind or steer
in the rod the amount OF electrihcation
paSSeN over the copper WIG, tiiS eihS
occupied and other conditions. What you
10 with the steel rod and the copper
wire the sun is daily doing to the earth
The copper coll is helix. IL you trace
The path of the suns vertical rays, the
RAYS of greatest energy. on the surface
of the earth you will find that this makes
a spiral coil about the earth 1t begins
At perihelion, in the tropic Of Capricorn,
January l. and winds northward TO the
tropic of Cancer, July /, when ii turns
southwark and winds back again to the
tropic of Capricorn. There are 1856 winds
in all In other words. the sun Is and
has been for millions of years doing on
a gigantic scale to the earth what you
nave done for few moments to the
steel rod with this difference. that IL is
a globular structure instead of rod that
is being affected. IL while you are con-
Quoting your experiments with the rod
there be in the room other magnetized or
magnetizable objects each of them will
affect the magnetization of the rod ac-
cording to their size. permeability and
distance from the rod.
Similar Effect Produced.
This is what happens in way with
the earth. The solar system is the room
i'm which the operation is done, and il
has it's own magnetic state which af-