Continental drift plate tectonics theory. In particular, the English geologist Arthur Holmes proposed in 1920 that plate junctions might lie beneath the sea, and in 1928 that convection currents within the mantle might be the driving force. Holmes' views were particularly influential: in his bestselling textbook, "Principles of Physical Geology," he included a chapter on continental drift, proposing that Earth's mantle contained convection cells which dissipated radioactive heat and moved the crust at the surface. Holmes' proposal resolved the phase disequilibrium objection (the underlying fluid was kept from solidifying by radioactive heating from the core). However, scientific communication in the '30 and
Drift hypothesis at supported the drift hypothesis, but when he examined them, he found their conclusions were "based on assumptions and methods that lacked empirical support." Another statement in Fox's study was, in studies done on social class and mental illness, "identify drift as an individual's downward intergenerational social mobility after the onset of mental illness, rather than as residential drift from higher to lower class status areas". So depending on what one's definition of drift hypothesis is, there will be data either to support or refute the validity of it. From an economic perspective of social class and mental illness, the