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
The Continental Op The Continental Op The Continental Op is a fictional character created by Dashiell Hammett. He is a private investigator employed as an operative of the Continental Detective Agency's San Francisco office. The stories are all told in the first person and his name is never mentioned. The Continental Op is a master of deceit in the exercise of his occupation. In his 1927 "Black Mask" story "$106,000 Blood Money" the Op is confronted with two dilemmas: shall he expose a corrupt fellow detective, thereby hurting the reputation of his agency; and shall he also allow an informant to collect the