Herschel and Babbage theory of mountain building, 123.
Herschel, Sir W., on galaxy of milky way, 293.
Hertz, negative electrification discharged by light, 204.
Himalaya, geological history of, 134-139.
Hobbs, on association of earthquakes and geosynclines, 143.
Holmes, A., original lead in minerals, 20; age of Devonian, 21.
Horst concerned in Alpine _déferlement_, objections to, 156.
Hyperion, dimensions of, 177.
I.
Ice, melting of, by pressure, 267 _et seq._; expansion of water
in becoming, 267; lowering of melting-point by pressure, 267;
fall of temperature under pressure, 268 _et seq._; viscosity of,
284.