Atmosphere, compressibility of, [8].

Attack, of the weather, [149].

Atwood, W. W., cited, [7], [160], [298], [300], [313], [372].

Axial plane, of folds, [42].

Axis, of folds, [42].

Azurite, [453].

Bacteria, part taken in weathering, [156].

“Bad Lands”, control of relief in, [223], [224].

“Bad Land” topography, [214].

Bajir, [216].