The morning news. [volume] (Savannah, Ga.) 1887-1900, 1898-06-04

Maine to Mobile. It's line cuts down aIong
the Appalachian region and runs firm the
northeastern corner of Maine TO Mobile.
Another is the transcontinental arc
winch starts at Cape May and goes on the
thirty-ninth parallel to San Francisco,
which Is something rather unique in that
the longest line ever observed in both d.
rections is found thereon. That line is
Is5 miles long, extending from Mount FL
len, having an eleva tIon of II 900 feet 10
UncOmpahgre, which is about 1900 feet
high. The accuracy that is attained in
. this work is remarkable There are in
eVitable discrepancies in the measurement
OF angles, and il is supposed that you can
not preserve the accuracy of the base line
forever, but in this obHque arc they meas
uTed a base line at Kent Isle Maryland
and another at Atlanta, Ca, and they
carried out this triangulation of each base
toward the other, and met somewhere in
North Carolina to compare the meeting
lines. They could calculate on either base
and the result was that the lines, about
thirty miles long, showed a discrepancy
between the two measures of not more
than half an inch. The two sets of OBJ
servers were each so anxious to get out
the results first that as soon as calculated
they mailed the length, or rather the dog
arithm, and the two letters crossed each
other on the road, which shows that there
was no fixing up the figures in reaching
this remarkable result
THE International Geodetic Association
is studying the effect of refraction and
alteration, the variation of latitude and
other kindred subjects. At the next meet
ing in October they will take up the va
Ration of latitude, and the idea is to de-
termne CHS by having four International
stations all on the same parallel of lati-
tude when is going to be SO g. a little
| north of Washington, near Rockville. Mo.
| Two of these stations will be in the United
States, one in the East and one in the
| West, one in Japan and one in Sicily. The
coast survey will have charge of the two
| in the United States; all the observations
| will be reduced in Europe under the direc-
ucn OF central bureau When the coast
survey studied these problems before, in
conjunction with the Germans, each gov
ernment sent man to Honolulu, and
another man from each was sta
| toned at Berlin. They observed
| every night, when they could get stars for
two years, and the two men at Honolulu
ana the two men at Berlin brought back
results so opposite in character as fully
10 establish the fact that there was a slight
Vibratory motion of the pole, independent
of the regular movements of the earth It's
period is 427 days 1t has been known since
| 1888, but we can go back to observations
made forty years ago and see the effect OF
the same fact Nobody was then bold
enough to say that the latitude changes.
for that is what the movement of the pole
means Mr.. s. G. Chandler of Boston, edi-
tor OF the Astronomical Journal, is the best
authority in this country on the polar mo-
tion. He made obserVa lions with an instru-
ment hoating in mercury, so as to avoid
! having to make the correction for level.
and made some very accurate observations
After he had registered them, he seemed
to think there was evidence that the lati-
tude changed, since that was the only way
he could explain certain DISCREPANCIES in
his results, but he did not make the as
sertion absolutely The Germans examined
the matter very closely, and from contin-
| ued observations for two years announced
| in about 1888 that the latitude changed
| This, which was at first received with in
credulity, is now admitted on all sides.
In the same way the tetrahedral theory
! is going through a period of probation. ]
| am not prepared to say that I accept it,
! and, If proved the amount Of modification
/ of the spheriodal form of the earth in thai
! direction will be very slight of course But
| we know that the equator is not a perfec,
| circle, rather an eilipse, and the tetrahe-
/ dral theory accounts for some things not
| otherwise easily explained Measurement
| OF the ffty-second parallel in Europe
/ showed that that arc had radius of over
400 meters less than in the Clarke figure
and then they measured another arc on tht
same parallel with n like result The evl.
! dence was unmistakable as far as it went
| This arc in America seems to show the
same thing. The shrinking of the earth is
| a geological question rather than a geo.
! detic, but L believe ii is scientifically ad.
mitted that such process is going on. Bu
our coast survey service is primarily fol-
the making of maps, and 1t is one Of oul
| first duties to determine the size and shaD,
of the earth, upon which all else depends
and hence the great and painstaking exper
iments which the government is conductinl
with the other governments of the world