Morgan County Democrat. (McConnelsville, Ohio) 1886-1943, 1931-12-17
This Wobbling Earth

Mali anu the STARS
This Wobbling Earth
Terra firma may not be so firm as
it is generally supposed, if the re-
suits of studies now being made at
the Perkins Observatory become sub
stantiated through the further in
vestigations now in progress.
Time was when man thought that
he dwelt on very firm earth fixed
in the universe. Astronomy has now
long taught mankind that the earth
is anything but fixed. Now the
would be watcher of the celestial
drama knows that he occupies but a
tourists seat, enjoying one of the
grandest sight seeing trips through
space imaginable. Spinning around
the earth's axis at six hundred
miles an hour lin latitude forty
degrees and running a race course
about the sun at speed of eighteen
miles a second, the observer climbs
a spiral celestial ramp ascending
towards the star Vega at a speed Of
10000 miles an hour, while the
whole galactic system makes a
celestial voyage through space at
probably thirty times this speed.
Now it appears thai the sight
seeing car in which we are riding
is bit unstable, that the earth's
crust may after all be sort of loose
skinned affair which yields to the
pull of the moon in the sky much as
do the tides in the ocean. These
conclusions have been reached as
the result of careful analysis of
many thousands of observations of
the determination of latitude on the
earth's surface.
Perhaps the most precise guam
tity which can be measured as
Economically is the exact latitude of
a given point on the earth. This
the astronomer measures by deter
mining with great precision through
the telescope the exact point in the
heavens over the plumb line, or
the vertical. 1t is now found that
the apparent direction of the yer
t1cal among the stars appears to
depend in some mysterious way
upon the position of the moon in
the sky, the vertical being ben;
slightly away from the moon as it
rises, and progressively changing as
the moon changes it's position. Such
state of affairs may be explained
as a very minute but real variation
in the latitude of the observer due
to a possible displacement of the
earth's crust under the gravitation
al attraction of the earth's satellite
1t has long been known that mi
mute tides must exist in earth on
theoretical grounds, but the chang
ing latitude observed in these re-
cent studies appears to indicate q
displacement considerably greater
than what would be expected if the
earth were rigid throughout.
For some time biologists have
been suspecting that while the in
terror of the earth is probably as
rigid as steel, there may be semi
fluid layer Immediately beneath the
earth'S crust, some seventy miles
down. The possibility that tides in
this semi-mobile layer may be re
sponsible for the apparent shift of
the vertical, as observed in daily
latitude variations, gives the prob
lem geophysical as we'll as as
Economical interest
Years ago scientists discovered
that the position of the north pole
Of the earth changed slightly in the
course of year, describing rough
ly circle something less than sixty
feet in diameter. Present investi
cations seem to show that in addi-
ton to this relatively long-period
effect, there is indeed an hourly
variation which correlates with the
circling Of the moon about the
earth This variation would cor
respond to a surface displacement
in the earth's crust of from five to
ten feet Whether or not such is
actually the case, or whether there
is some other explanation of the
mysterious change for the direc-
ton Of the vertical with the rising
moon, must await the outcome. of
the analysis Of many hundreds Of
observations that will be undertak-