Planet, slowing of axial rotation of, 189.
Plant, expectant attitude of, 109.
Pleochroic haloes, measurements of, 224; theory of, 224 _et
seq._; true form of, 226; radius of, and the additive law, 225;
absence of actinium haloes, 225; see _also_ Haloes; mode of
occurrence of, 223 _et seq._
Poole, J. H. J., proportionality of thorium and uranium, 26.
Poulton, uniformity of past climate, 17.
Pratt, Archdeacon, and isostasy, 53.
Préalpes, exotic nature of, 150, 151.
Prematerial universe, nature of a, 297, 300.
Prestwich and thickness of rigid crust, 128; history of the
Pyrenees, 140.
Primitive organisms, interference of, 89; life-curves of, 88.