Published online by Cambridge University Press: 01 May 2009
In Part IV of this paper the theory that the earth has continuously cooled down from a former molten state was shown to lead to limitations of temperature and to a distribution of rock-types at moderate depths which, taken together, made it impossible for igneous activity to have taken place as we know it to have done. It was argued that this conclusion definitely proved the theory to be wrong. Now, instead of deducing the distribution of rock-types in depth from their radioactive contents, the method of attack will be reversed and an attempt will be made to determine the downward distribution independently, so that the radioactive effects may be deduced without reference to any limiting hypothesis of a steadily cooling earth.
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