Evening star. [volume] (Washington, D.C.) 1854-1972, 1903-06-13
EARTHQUAKE SURVEY
Latest Scientific Enterprise
of the Government.
A CHAIN OF STATIONS
INTERESTING NEW INSTRU-
MENTs ARE BEING INSTALLED.
Will Increase Our knowledge of the
Earth's Crust and It's
Interior.
A CHAIN OF STATIONS

Copyright, 1903, by John Elfreth Watkins, jr.)
Written for The Evening Star.
An earthquake survey on a grand scale is
the latest scientific enterprise of the gov
eminent Traps are to be set for seismic
disturbances in all corners of our vastly
scattered domain. A brand new one has
been set up in Washington; another at
Honolulu. Others are to be presently in
stalled at the governments new magnetic
observatories at Cheltenham, Md; Bald
win Kan: Vieques Island. Porto Rico, and
Stka, Alaska.
At Philadelphia, Baltimore and Manila
are three private stations, which Will CO.
operate with these six in the official chain.
The Quaker city's station is at Swathmore
College; that of the monumental city, at
John Hopkins University, where 1t is in
charge of Prof. II. F. Reid, the leading
American authority on earthquake phe-
nomena The Manila station in in charge
of Father Algue a Jesuit scientist of the
Manila observatory At Toronto and Vic
toria B. c. are two stations under the
meteorological establishment of Canada,
which will cooperate. Others at Mexico
City; Cordoba in Argentina, and Arequlpa,
In Peru. also Will contribute Information
Thus not only our insular possessions out
our continental area and its surroundings
earth sets up any quaking within our boun-
daries we will know of 1t.
New Earthquake Traps.
Earthquake traps of an entirely new pat
tern have been selected for the government
stations One of these is already doing
work in a dark subterranean dungeon
under the national weather bureau, where
II caught a seismic disturbance few weeks
ago Another is being tested in the base
ment of the coast and geodetic survey,
whence II is to be shipped to Porto Rico In
a week or two There 1t will watch the
troubled earth crust of the Antilles, In
whose chain Mont Pelee and her consort
wrought such wholesale slaughter a year
ago
The new instrument adopted by the gov
eminent is regarded as the most perfect or
its kind It Is . modification of the one
perfected by Prof. Omori. secretary of the
earthquake investigation committee of ia
pan. Japan is the great earthquake coun-
try, and has gone so far as to found
chair of sesmoogy-the science of earth
quakes-in the University of Tokyo.
This new trap consists of heavy weight.
so suspended in front of tall iron pedos
tai as to be always In neutral equilibrium
and unaffected by any influence other than
gravity. While the earth is quakins d.
rectly below ii II is standing still for the
moment. 1t is SPAWNED by iron arch.
whose base is a stone pier penetrating into
the earth. Earth movements are directly
communicated to the arch. Hence, when
even the slightest earth tremor takes place
the arch moves herewith and the weight
below remains quiet suggested At
tached to the stationary weight. by jew
eled pivot. is long, slender arm of alu-
minum. with a writing pen at it's outer end.
Upon the same foundation with the arch,
and sharing all earth movements with 1t,
is n revolving wheel whose tire is of paper.
The writing pen rests against this paper.
The principle of the instrument. In nut
shell. is that earthquakes move the paper
against the pen and record the earth's
tremors in zgzags or curves. But by
delicate adjustment of the aluminium arm
II is made to eXaggerate the earthquakes
tremor to a measurable degree. The wheel
with Its paper tire makes one revolution
every hour The writing pen starts it's
record on one edge. and by means of
thread on the wheels axle is made to Grad
ually trace spiral over the paper. unless
an earthquake interrupts it Thus, the
normal lines Of the pen do not overlap Ry
means of an electromagnetic attached to
specially made clock current is COM
municated every minute to another pen
point The latter gives jerk when 1t re-
ceiVcs the current and thus checks off min
utes along the spiral line traced by the
first pen mentioned. A new paper tire is
put on the instrument at the same min
ute each day. Thus, knowing when a
new record is set. the exact time of a zig
Tag earthquake record can be determined
by counting the minute marks on the
paper
sary fer each station. One always pointed
north and south, records earthquake vibra-
lions moving east and west; the other di-
rected east and west. records north and
south vibrations. An earthquake will make
a record on both instruments at once
The Zig-Zags will differ. but the two paper
records Will be taken from the wheels and
delicately compared with a scale. The ex-
act direction of the earthquake and the
width of its horizontal waves can thus be
estimated to nicely
One Quake Lately Trapped.
The earthquake trapped by this new
seismograph at the weather bureau was
snnoticed by the public. 1t was not report
cd IN the newspapers. and would never
have been discovered In this part of the
world had not an instrument as delicate
-ss his been In place. The seismoeranh
vas Installed in the latter part of Febru-