Abrasion, beneath glaciers, [275].
Abyssinia, fissure eruptions in, [101].
Accordance, of tributary valleys, [162].
Adiabatic refrigeration, in relation to glaciers, [262].
Adolescence, in cycle of erosion, [169].
Advancing hemicycle of glaciation, [263-266].
Advective zone, of atmosphere, [270].
Aftershocks, of earthquakes, [83].
Agassiz, glacial lake, [325-328].