Talchir boulder-bed, 136.
Temperature gradient in Earth's crust, 126.
Termier, section of the Pelvoux Massif, 254.
Tethys, early extent of, 135-137; geosynclines of, 142.
Thermal metamorphism in Alpine rocks, 132, 149.
Thomson, James, prediction of melting of ice by pressure, 267.
Thorium and uranium, proportionality of, in older rocks, 26.
Triple canals, formation of, by attraction of a satellite, 187.
Tyndall, colour of ocean water, 55.