The Hawaiian star. [volume] (Honolulu [Oahu]) 1893-1912, 1901-08-10
TO WATCH THE NEEDLE THEY WANT EIGHT HOURSS
ANOTHER FEDERAL SCIENTIFIC
INSTITUTION.
The Magnetic Observatory at Pearl
Harbor and What it Will Accomplish
and How-Delicate Instruments.

The magnetic observatory to be es-
tablished near the sea beyond Eva will
have study as its principal object.
Variations will be recorded and COM
PARSONS made with other stations. The
study of magnetic variations is now en-
gagged in by most nations, and the Unit
ed states is taking a particularly active
interest in the matter. Stations have
been established at WASHINGTON and
various parts of the Union and obser-
vatories are being erected. The one in
Hawaii will give a chance for study in
the mid-Pacific.
In the past naval vessels, of both the
American and English fleets, have been
in the habit of making experiments
here and reporting such variations as
appeared at the time of their visits.
The observations were usually made
from a point opposite the Waikiki end
of the judiciary building. The survey
department also kept up with the vari-I
ations, but in crude way, not having
the proper equipment with which to-
operate.
According to Prof. Alexander the va
riations operate from east to west and
then back again. The general trend of
the variations is westward the meri-
dian having moved from Washington
nearly to Cincinnati in the past few
years. Although numerous theories
have been advanced no one has satis-
factorily accounted for this change.
The general shifting from east to west
and back is accounted for by the reVo-
lutions of the earth around the sun,
and comes in cycles. This has been
established and is no longer a theory
OF the local observatory Mr.. Fleming
says: THE establishment of this mag
netic observatory is important from a
Scientific standpoint, and has particu-
lar interest for mariners and other
travellers. 1t will mark all changes of
the compass from the true north to the
magnetic meridian. Sailors will appre-
ciate the corrections thus made, as
charts drawn ten or fifteen years ago,
giving bearings reckoned on a basis
of observations made at that time, are
now in many cases practically worth
less, as regards their bearing.
''As is generally known, the point
of the compass is not fixed. In Maine
| the declination, or as it is known, var1-
alton, will reach 20 degrees west of
north, while in Oregon it will vary even
more in the opposite direction. 1t is,
! for the purpose of registering these
! and other variations that the treasury
| department decided to construct four
| magnetic observatories. One has al
ready been built near Cheltenham,
Md, one is to be built on the Allan
II,
| nolulu.
"The observations to be taken are
! divided into three classes. the declina-
! ton, inclination and horizontal force.
! The declnation is the difference be-
| tween the true north and the magnetic
meridian. The inclination, or dip. is
| the angle between the horizontal and a
straight line drawn from the Observers
! position to the magnetic pole. The
horizontal force is the pull of the earth
| laterally on the needle.
| The instruments necessary to record
such minute variations and forces will
be most delicate in their mechanism
yet their action is equally as simple.
They consist of very small magnets
suspended by fine quartz fibers so as
to swing freely. To each magnet will
be attached a tiny mirror. A small ray
of light is thrown on each mirror from
| a fixed point. This light is reflected
on a revolving cylinder to which has
been attached a sheet of Photographic
paper. In this manner each movement
of the magnets is photographed, thus
recording perfectly the declination, in
clination and horizontal forces.
! THE building containing these in
struments will be specially constructed
] to defy all changes in temperature. The
! instrument will be in a room having
walls, ceiling and floor one foot in
thickness and packed with sawdust
Outside will be a two-foot passageway
] and then a wall one foot thick also
: packed with sawdQst; then there will
be a siX-inch air space and then, the
= exterior walls. No iron nails will be
l used Instead all metal work will be OF
= copper, in order that the building may
. be non-magnetic. About twenty-five
l tons of sawdust will be necessary in thu
construction of the building.
E 1.-THE work of the division of terre
D strial magnetism is in the hands of DR.
} L. A. Bauer, who has given the sub
r ject thorough and expert study, botf
e here and in Europe. Dr.-Bauer wa'
in Honolulu last October and selected
the sit for the observatory, Prof w
d. Alexander, will have general sup
!, ervision of the observatory I will re
q main here one year. The observator'
will probably be in working order with
n in three months"
a Prof Fleming stated that to keep al
p even Temperature in the observator'
considerable ice would have to be used
In Alaska, on the other hand, hea
was sought. Heat has the effect o
detractfng from the magnetic force
: While cold increases the force. To oh
tain correct results an even tempera
ture is necessary. Prof. Fleming say
he has struck one snag here in the eX
cessively high price of lumber.