The sun. [volume] (New York [N.Y.]) 1833-1916, 1914-03-15
I carrying magnetic instruments.

serNatiOns as Yet on WhiCh 10 base
definite statement. But 1t would he
singular indeed II these points remained
fixed and were not affected by fuctua-
tons such as are now known from three
centuries Of observations To exist in
every one of the earth's magnetic phe-
nomena. II is quite possible, in fact
that the magnetic poles pass through
certain motions even in the course Of
day or suffer displacements during mag
netlc storms
ny curves which have traced show
ing these movements at certain points
during long periods Of time IA number
OF interesting and instructive facts come
to light. For Instance. IL IL seen that AZ
London the compass reached its maxi
mum easterly direction Of about IL de-
grees in the year 1850. hence during the
middle Of Queen E:llzabeths reign;
thereafter the easterly direction began
to diminish until about 1858. the year of
Cromwell's death. when the needle bore
due north and then swung over TO the
west. continuing to do 40 until 1t reached
a maximum westerly direction of some
what over - degrees in about 1872.
Hence in the interval Of about 232 years
15S0-1Sl2) the compass direction
changed at London from II degrees east
to - degrees west. or 81 degrees.
AT the present time it points about
l5h degrees west. or nearly . degrees
less than in 1872. and a most interest,"
ing question doubtless Immediately oc-
ours to all Of us: Will the freely sus-
pended agnetic needle ever return pre-
cisely to a direction taken at some
previous time or is there any definite
hn ts.hi ,b ui sAlf
from time to time?'
In other words, has the magnetic
pole and have the local magnetic read
ings Of different points upon the globe
movements akin to the sweep Of a very
slowly swinging pendulum? tnfortu-
nately science can't answer this ques-
ton now. but the work OF the Carnegie
Institution is probably going to help
nightly toward the solution Of this
riddle In the future.
From DIR. Bauers diagram 1t is
learned that in the United States the
changes in the compass direction, as
far back as they are known, have not
been as great as those during the same
time in London. Thus at Baltimore
the compass appears to have reached IA
maximum westerly amount Of about 6.1
degrees near 1870 and n minimum Of %
degree in 1902. after which instead Of
passing through n zero value as at Lon
don in 1853. and swinging Ia the east
ward 1t turned back and began to in
crease its westerly direction until at
the present time the amount is about
GU degrees. Thus at this station the
compass direction passed from a maxi
mum to n minimum In about 1872 years
and the total change was 5la degrees.
or only One-siXth to one-seventh OF
that at London.
Now this question OF compass varia-
ton, or declination. as II Is technically
termed IL not a thing to concern alone
the navigator. The surveyor must con-
slider this movement OF the compass
when running anew lines specified in
old deeds or grants of land. This be-
comes more and more important as
centres Of population move into the
country beyond where metes and bounds
have not been checked up in many in
stances for generations.
The Carnegie Institution began this
work in 1905 when it fitted out the
brigantine Galilee Of San Francisco and
sent her out to explore magnetically the
Pacific Ocean. For nearly three years,
from August Of 1905 until May Of 1905
the Galilee covered Go. 600 miles OF the
Pacific. and the success OF that vessel
led to the designing and the cons,ruc-
ton OF the non-magnetic yacht Car
negie.
During her first cruise the Carnegie
logged 1000 miles, and the total work
Of both vessels, including the Carnegic's
extra ordinarily long voyage recently
ended, covers a matter OF l60, 900 miles.
The routes have looped and circled
throughout the Atlantic, Pacific and
Indian oceans In order that the inter-
secting courses might facilitate the
checking and counter checking Of pre-
ccdire observations
Time was of little concern The Car
rcLie might drift when the wind failed.
sail when the breezes favored, or head
her way into the gale or reach her
GOAL wien n calm prevailed under the
impulse of an internal combustion en-
sinc built we'll nigh entirely Of non
magnetic metal. That the necessary
obser, atoms might he made with q de-
gree OF nicely and an amplitude un-
dreamed Of in the days OF HALEY spe-
Cial instruments were designed and
fashioned for the Carnegie. and with
these It has heen possible to observe
and to read the three magnetic ele-
Tents ~ declination, dip and intensity.
Declination il the variation from east
to west. dip the downward pointing OF
the north end ~ the needle and inten-
sity the measure Of the disturbing
force.
because Of these facilities. Dr. Bauer
says 1T has been possible to achieve