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

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EARTH'S SHIFTING CRUST
principle is not that usually presented in high
school and
college textbooks of physics. The definition of the law of the
parallelogram
of forces is as follows:
If two forces acting on a point be represented in direction and
intensity by the adjacent sides of a parallelogram, their resultant will
be represented by that diagonal of the parallelogram which passes
through the point (249:489).
In the three parallelograms in Figure XII, the two forces
acting on the point a are the force of gravity, represented by
the line a-d (a radial line to the center of the earth), and the
tangential component of the centrifugal effect of the icecap,
represented by the line a-c, while the "resultant" of these
forces is the diagonal a-b, at right angles to the axis of rota-
tion. The reader will note that Campbell has here inverted
the terms of the definition but without changing the quantities
of the forces in relationship to each other. The "re-
sultant* '
in the definition is our starting point; it is the
estimated total centrifugal effect of the icecap. But it is evi-
dent that it is unimportant whether the given quantity is the
diagonal or the side of the parallelogram; the parallelogram
permits the finding of the unknown quantity from the known
quantity, whichever the latter is. The parallelogram therefore
permits a finding of the quantity of the tangential com-
ponent. The rotating effect of this force exerted on the
earth's crust is illustrated by the weight shown in Figure XIV.
By definition, the tangential component of the centrifugal
effect is exerted horizontally on the earth's crust. Now the
arises as to whether this force will be exerted on
question
the crust itself, or whether it will act on the earth's body as
a whole, and thus tend to be dissipated in depth. This is the
same as the question whether the icecap will tend to shift the
whole planet on its axis or merely to shift the crust. We have
already decided that it will tend to shift the crust only, because
of the existence of a soft, viscous, and plastic layer
under the crust. We may therefore conceive of this force,
the tangential component of the total effect, as acting on the