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

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EARTH'S SHIFTING CRUST
the earth's surface has as yet received an acceptable explanation.
As in the case of other unsolved problems, the absence
of certainty has led to a multiplicity of theories. Jaggar, one
of the best field observers of volcanoes, refers to the two
leading
theories thus:
It would be hard to imagine any more completely different ex-
doctrine of
planations for the same phenomenon than is R. A. Daly's
the causes of volcanic action, as compared with the crystallization
theory of A. L. Day (235:150).
Dr. A. L. Day was formerly director of the Geophysical
Laboratory in Washington; his theory is based upon geophysical
experiments conducted in the laboratory. He observed
that the crystallization of rock from the molten state
resulted in some increase in volume. He assumed that the
whole crust was once molten, and that as it cooled it continued
to contain, here and there, comparatively small pockets
of molten rock. When such pockets of molten rock finally
were cooled to the crystallization point, then expansion
would occur, and great pressures would be set up, which
might lead to eruption at the surface. This theory is based
upon the assumption of the molten origin of the earth, and
carries with it the corollary that volcanic eruptions are essen-
tially local phenomena. Dr. Day insisted that volcanoes were
not connected with a molten layer under the crust, and were
not related to events occurring over large areas.
Professor R. A. Daly based his opposed theory on his ob-
servations of the field evidence of geology. He insisted that
only the assumption of a molten layer under the crust could
account for the countless facts of igneous geology. His theory
is reconcilable either with the assumption of the molten ori-
gin of the globe or with the theory of a growing and heating
earth.
Jaggar objects to Day's view that volcanoes are purely lo-
cal. He says:
There is some reason to think that a very long crack in the bottom
of the Pacific Ocean, with interruptions by very deep water, extends