Pompeii, destruction of, [97];
volcanic materials over, [122].
Ponores, [188].
Porphyritic texture, of certain igneous rocks, [32].
Portals, in mountain rampart, surrounding continental glaciers, [271].
Potato shape, of earth, [7].
Pourquoi-Pas expedition, [289].
Powell, J. W., cited, [178], [439], [446].
Pratt, W. E., cited, [147].
Precipitation, in relation to glaciation, [261].