The times., 1901-05-12

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herst party sailed 10000, carrying an
equipment of delicate and valuable in
! struments. and then We're disappointed
because just at the critical moment there
was a bit of white cloud in the line of
I the eclipse The meteorological record of
Sumatra is good and under the law of
probabilities the astronomers have reason
to hope for clear day on May H., Dut
there can be no assurance beyond hope
based on this fair probability
technical school to send party to OBJ
i serve an eclipse OF the sun, whether at
! the antipOdeS or nearer home. but the eX-
pedition is. in fact, quite in line with the
. recent policy OF the Institute of TeChnOl-
. ogy Moreover, the institute has a Ger
( tain amount OF money which is available
only for special scientific research, and it
is from this fund that the expenses of
I the long voyage have been betrayed, in
the hope that something valuable might
be~done in the region of pure science.
/ The eclipse last year offered an oppor-
/ tunity for making observations compare
lively near home, and incidental TO the
! astronomical work some geodeuc work
! was done For example, in illustration
of this latter point it was known that
the maps of the part of Georgia in the
! neiShborhood of Washington were not
controlled by triangulatiOn ana il was not
expected that the latitude and longitude
of the station could be accurately scaled
from them. Prof. Burton, therefore. made
an independent examination, obtaining
the latitude by means of an astronomical
transit and the longitude by time sig
nal from Washington, d. c. This deter
miuatiOn placed the location of the ObSerV-
ing station some four miles north and
nearly two miles west of the map loca-
ton. and of the central line of the eclipse
, sufficiently to reduce the period Of COM
pUted tOtality about two seconds.
While the present party Is prepared TO
undertake similar corrective determine
tionS IN Sumatra. the chief purpose is
independent astronomical work. This will
consist Of observations of the four con-
facts, namely, the first contact when the
edge of the moon touches the edge of the
sun, the second contact, or the beginning
of totality. when the sun is first COM
pletely hidden; the third contact, or the
end of tOtaiity, when the rim of the sun
is about TO emerge from the shadow; and
the last contact, when the edge of the
moon separates itself from the edge of
the sun. With the first contact grow
ing darkness advances steadily toward
the spectator the birds as one writer
describes it, fly silently to their nests, and
all nature seems TO take on the hush of
sudden night. A little golden rim of the
sun is visible up to the moment of the
second contact. When that disappears
the corona. about which so much has been
written by all who have described to-
tai eclipse, seems to fash out from the
black disc of the moon with a wonderful
and almost unearthly beauty.
The corona, supposedly. is a permanent
phenomenon but Il Is not revealed until
the last rays OF the sun are hidden. There
are really two COronaS, the inner corona,
which seems TO surround the moon like a
sends out faint streamerS OF light far into !
the darkness of the heavens. What the
corona is or what its causes are nobody
knows, but the strange Coronal light has
awakened the curiosity of the astronomers
Of many centuries Within a comparative
~ few years il has been possible. however,
to photograph this phenomenon. and Mr..
Smith. the photographer of the institute
expedition, has introduced novel methods |
for mounting the camera and making II
follow the apparent motion of the sun.
n had
before been possible, so that ne is hopeful |
of particularly valuable and interesting re- |
suits. 1t is possible also that he may un- |
dertake 10 photograph those mysterious |
waves Of darkness and light which precede |
totality and are called shadow bands.
This is a task not known TO have ever /
been undertaken. although some attempts /
have been made at Cambridge TO study |
the principles involved as Illustrated in ar |
uhcial shadow bands produced by means |
of q distant flash light.
An eclipse is such an unusual and elu- |
siVe phenomenon that ii is studied by |
nearly every scientist who has a special |
physical problem on his hand, with a view |
10 finding some tangible clue to a solu- !
tion of his special difficulties. From such |
a purely experimental standpoint obser- |
VatiOns in magnetic variation were made |
in this country during the last eclipse by |
students Of terrestrial magnetism stationed |
II intervals along the path Of the shadow !
The results of the observation at that |
time have been analyZed by Mr.. l.. a. |
Bauer, in charge Of the magnetic work |
of the United States Coast and GeodetiC |
Survey. who has arrived at the conclu-
sion that the apparent magnetic variation.
as shown in the dip and deciiuatiOn of a
magnetic needle hung from silk threads,
was not without distinct scientific signifi-
canoe While Mr. Bauer does not as yet
present a working theory, he is compelled
TO believe that the oscillation observed
during the eclipse was not accidently con-
nected with it. but was indeed brought
about by some change which took place
In the upper regions of the atmosphere
by the withdrawal therefrom of the suns
rays, ana has made arrangements Tor
careful observation all over the world |
during the eclipse next Friday. As the
institute party made magnetic ObserVa- !
tiOus during the eclipse. so 1T viii under
take the same work this year in Suma-
ira. and at the same time similar obser- |
VatioHs VIII be made al its gcodetiC OBJ
Servatory in the Middiese1 Fclis near
Boston
Another interesting piece Of work which
this party viii carry out at Sumatra
though not directly connected with the
elipse. viii consist Of measurements Of
the force Of gravity by means Of the
pendulum apparatus which has been lent
by the Coast and GeOdetic Survey
Pendulum observations Of this kind. how
ever, have been made at many points,
both iu the United States and in Europe
ia recent expedition to Greenland and
Labrador, for example, Prof Burton
made q number Of observations Of this
character, and he hopes 10y similar OBJ
observations in Sumatra to introduce "A
connecting link in the calculations already
made
In preparing the present expedition.
the institute has had the cooperation Of
the Harvard Observatory, through it's
director, Prof j.. G. Pickering Photo
graphic lenses and other instruments
have been lent to Prof. Burton for the
work in Sumatra. and the plans Of a new
form Of synchrOnized driving clock the
joint invention Of Prof. Pickering and Mr..
w. =. Gerris. Of Harvard have been
placed at his disposal. 50 that he Will be
able TO equip his instruments with this
device, which is, briefly an electric motor