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

EARTH'S SHIFTING CRUST
tions from the general theory of crust displacements, and
may be incapable, at least at this stage, of direct proof.
2. The Views of the Geophysicists
In this civil war between the sciences, the first group I shall
call upon to present their side of the case are the geophysicists.
Now the geophysicists, by and large, have very definite
views about the continents, even though they cannot explain
their origin. Their consensus is that the continents have been
permanent features of the earth's crust from the "beginning,"
and this involves an equal permanence for the ocean basins.
Changes of sea level there have been: so much cannot be denied;
but according to the geophysicists these can have been
only relatively important. At times the continental shelves
(the narrow strips along the coasts where the water is only a
few hundred feet deep) have been laid bare, and at other
times the oceans have invaded the low parts of the conti-
nents, but such changes (while unexplained) have been
slight; they have not affected the main masses of the continents.
The continents, then, are original features dating, in
their present positions, from the unknown beginnings of the
planet.
Of course, geophysicists would never make such broad
statements as these, unless they had what seemed to them
sufficient evidence. Their argument is easily stated. They
point to the differences in composition. The continental rock
is less dense, on the average, than the rock under the oceans.
The force of gravitation brings all sectors of the earth's crust
into rough balance, and this means that the lighter parts will
stick up higher, like pieces of wood or ice floating on water.
The continental sectors of the crust are considered to be both
lighter and thicker than the oceanic sectors. The greater
thickness makes up for the less density, so that things bal-
ance off.
This principle of the gravitational balance of the crust is