The Earth's Shifting Crust by Charles Hapgood - wire of information

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EARTH'S SHIFTING CRUST
and therefore the effect of gravity at that point has not been
altered. A tangential component of this added centrifugal
momentum will tend to move this ice mass toward the
equator.
Eotvos applied this same principle to parts of the earth's
crust. We have seen that, according to the theory of isostasy,
mountains and continents are elevated above the ocean
bottoms because they are composed of lighter materials, and
are considered to be '
'floating" in an approximate gravi-
they
tational balance with the heavier crustal formations under
the oceans. Eotvos considered the centrifugal effects that
might arise from the elevations of the centers of gravity of
continental formations above those of the oceanic sectors of
the crust, and calculated them mathematically. He found
that the effects were comparatively slight. Attempts have
been made to account for the drift of continents through
these effects, but his calculations show they are too small to
have considerable effects. Since Eotvos' time, it has been
generally assumed that any centrifugal effects that were to be
considered in relationship to the earth's crust must be ef-
fects resulting from variations in the vertical position of cen-
ters of gravity of masses in gravitational balance, that is, ele-
vations of these centers above the equipotential surface, or
depressions of them below it, owing
to differences in relative
density of the masses involved.
Let us now consider, in connection with this, the effect of
departures of given masses from the state of isostatic or gravitational
equilibrium. We have already seen that there are
remarkable departures from isostatic balance, some resulting
from deformities of the crust, and some, it seems, from the
accumulation of icecaps. In these irregularities in the distribution
of matter, resulting from the limited failure of
isostatic adjustment, we must recognize the existence of an-
other surface of the earth, in contradistinction to the equipo-
tential or geoidal surface already mentioned. We may call
this surface the gravitational surface, or the surface of equal
mass. This is a real surface. It is not, however, the visible