The so-called geosyncline, or continental basin of sediments, filled with shells and strata as is the Mediterranean, is at the heart of all the theories of continents and mountains; and geology expressly excludes the geosyncline and its strata from the probabilities of deep ocean valleys. The most interesting subjects of continental geology are simply banished from conjecture. Interest in deep-ocean geology is lacking because science has made no field effort to bore or blast into it, and so extend engineering science to the deep ocean bottoms. Earthquakes made a theme wherein I instinctively distrusted the word “tectonic.” For generations the geological mind thought the earth losing heat, contracting internally, and wrinkling a crust in bumps, with vast overthrusts of broken strata, thus folding the Appalachians and the Andes. All sorts of accommodations to a thin crust thirty miles deep were invented; by Dana and Geikie, by Suess and Wiechert, and finally by one who should have been the foremost block faulting expert, Dutton. Hawaii convinced him that volcanoes are only skin deep and that the thin crust is so sensitive that a shift of the weight of river muds and sands is enough to push down the great valley of California, while an underflow pushes up the Sierra Nevada. This is the doctrine of “isostasy.” It agrees with the Stübel idea of shallow remnant reservoirs for the lava of volcanoes. Isostasy was devised by Dutton and pounced upon by the mathematicians, until they had gravity proving the whole world thin-crusted over an understratum of plastic lava. The seismologists on continents agreed, finding a density change, but with no evidence of fluidity. The world became, mathematically and petrologically, a sphere built of layers all the way down to the heavy fluid hot core, which was conveniently imagined to consist of iron and nickel, because some bolides of the solar system made of those metals occasionally fall on the earth.