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

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EARTH'S SHIFTING CRUST
of their density, with the lightest on top. Daly, in 1940, proposed
the following layering of the crust, at least under the
continents:
a. The sedimentary rocks, at the surface.
b. Below these a layer of basement rocks of granitic type,
ending about c.
15 kilometers, or 9 miles, down.
A third layer of rock, of somewhat greater weight, about
25 kilometers, or 15 miles, thick.
d. A fourth layer, about 10 kilometers, or 6 miles, thick, of
still heavier rock.
Having proposed these layers, however, he added that "the
exact depths of the discontinuities are not easily demon-
strated" and "it seems clear that each of the breaks varies in
its depth below the rocky surface" (97:17). In another place
he gave evidence of light matter at the very bottom of the
crust (97:223). These layers, then, according to Daly, are very
about them. On the one
peculiar. There is nothing regular
hand, he gives rough estimates of their thicknesses. On the
other hand, he indicates that these estimates are of little
value. They are, in fact, mere rough averages; they indicate
a trend toward increasing density with depth, together with
enormous confusion in the distribution of materials.
In view of the extreme uncertainties of Daly's view of the
structure of the earth's crust, it can hardly come as a com-
plete surprise that the most recent geophysical investigation
of the structure of the crust by the method of sound-wave
surveying has failed to show any distinct layering of the
crust. The geophysicists Tatel and Tuve have reported that
the results of the most recent studies, using the most recent
techniques, indicate that rocks of greater or less density are
intermixed in utter confusion, that the essential structure
of the crust is really that of a rubble, on a large scale (416:
107).
The main argument of the geophysicists who speak in
favor of the permanence of the continents, and, consequently,
of the ocean basins,
is based on the observed difference in