114 C. £. Dutton on the Contractional Hypothesis. 
oped, the yielding would take place at the lines, or regions of 
least resistance, and the effects of the yielding would be mani- 
fested chiefly, or wholly, at those places, in the form of 
mountain chains, or belts of table-lands, and in the disturbances 
of stratification. The primary division of the surface into areas 
land and water are attributed to the assumed smaller con- 
ductivity of materials underlying the land, which have been 
left behind in the general convergence of the surface toward 
the center. Regarding these as the main and underlying 
The argument of Hopkins is here accepted, that consolidation 
must begin at the center, as a consequence of the fact that pres-. 
sure elevates the congealing point; and temperatures being kept 
nearly uniform, the maximum pressure would determine the 
primary point of congelation. The solidification of materials at 
the surface would result in sinking by their increased density 
until the central solidification had proceeded so near the sur- 
face as to leave only an imperfectly liquid mass in which such 
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