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

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EARTH'S SHIFTING CRUST
ward effect would be thus counterbalanced? This is the crux
of the matter.
The answer to this problem may be found in the following
consideration. The force with which any object rolls down-
hill is proportionate not only to its weight but to the gradient
of the slope. On a flat surface the marble is at rest. It would
develop maximum momentum if it could fall straight down
toward the earth's center (if the surface were vertical). Be-
tween these extremes of zero and maximum momentum there
must be an even curve of increasing momentum with increas-
ing gradient. (It would follow, of course, that a sled would
develop twice the momentum if going down a hill twice as
steep.)
To apply this principle to the icecap, we may observe that
if there were no oblateness to the earth, there would be no
poleward component of gravity. If, on the other hand, the
oblateness were increased to the point where the icecap could
fall straight down, it would develop maximum momentum,
the product of its velocity and of its weight. Between these
extremes, the poleward momentum would be proportional to
the gradient. We have seen, however, that this gradient
amounts to only .017 per cent. It follows from this that the
poleward component of gravity acting on the icecap will be
.017 per cent of the tangential component of the centrifugal
effect of the icecap. This of course is a relatively negligible
quantity.
It may be objected that in this discussion we have offered
no mathematical calculations in support of the positions taken,
and that therefore we have no quantitative basis for our the-
ory. This is, however, a misunderstanding. It is essential, before
mathematical computations are made, to understand the
assumptions on which they are based. In our correspondence
we have more than once received communications in which
the authors have indirectly or directly stated that the question
as to whether a given mass was or was not isostatically com-
pensated was irrelevant. It has seemed to us, on the other hand,
that the actual balanced surface or shape of the earth as de-