The Salt Lake tribune. [volume] (Salt Lake City, Utah) 1890-current, 1910-06-19

g. To make special study Of regions
subject TO frequent earthquakes, with a
view to finding out where future earth
quakes are likely to occur.
!. To study tho origin of earthquakes
occurring under the neighboring oceans.
>. To organize parties to study in the
field the effects produced by large earth
quukes.
6. To study the best methods of build
ing in regions subject TO earthquakes.
This viii involve elaborate experiments.
Now. this matter of earthquake-proof
structures lis one of immense Importance.
In Japan and other countries new
knowledge on this. subject is being
extensively applied in the construction
Of tall chimneys, piers for bridges, reser-
voirs walls and dwellings. These new
types of structure have already proved
their value by withstanding violent
earth shakings. In California the merits
of reinforced concrete for resisting the
destructive effects of earthquakes have
come to be so well recognized that San
Francisco is being rebuilt of that ma
tcIial.
The most important instrument for
observing earthquakes is the "seismo,
graph. which automatically records
| even the smallest movements. 1t has
several forms. The one at the weather
bureau in Washington consists of long
rod thrust vertically into the ground,
which is so arranged, being piyoted at
] the bottom and weighted at the top
with mass of metal, that even the
| biggest quake cannot disturb its equl.
! lihrium But the stone pier through
which the rod descends necessarily
responds TO any movement of the ground
the result being that. in case of
shake. two fine steel points, attached
to the upper end of the rod. are made 10
joqgle over a slowly.revolving cylinder
covered with lamp. .blacked paper.
Tho cylinder, it will be understood.
keeps on revolving all the time. Thus,
under ordinary circumstances, the two
steel points trace straight white lines
along the lamp p-blacked paper. But any
movement of the earth will cause them
| TO wiggle. and thus the earthquake
writes, as one might say. its own sigma
ture. Resort is had to an ingenious de.
vice OF n mechanical kind for multiply
ing the effect Of the shock 100 times, so
that the earthquake s handwriting is
made proportionately large
Prof. John Milne, famous as an earth.
quake expert, saws that something like
10000 earthquakes occur in various
parts of the world every year. They
do a great deal more damage than is
commonly supposed. causing, says this
authority, an average loss of about 5000
human lives annually. not to mention
property destroyed. Many Of the most
severe shocks occur in the depths Of the
sea, especially in the great hollow
places, such as the abyss known as the
Tuscarora Deep, close by the east coast
Of Japan. Unfortunately, these sub
marine earthquakes (as has happened
many times in Japan) are liable to give
rise to great tidal waves. which rush in
over the land and wreak vast destruc-
tion.
1t seems likely, indeed that the
islands Of Japan were originally thrown
up, in the shape of lava. out of this
deep hole. In other words. Japan was
actually torn from the Tuscarora Deep,
which it would Just about fill. Similar
ly, the Aleutian islands seem to have
} been thrown up from under the ocean,
thus forming the deep trench close by
them to the south, which they would
: Just about fill if thrown in. AT al.
most every big earthquake in the Aleu-
tian region some one of the Aleutian