This is a digital reprint of the revised 1976 edition of this classic
work. It examines seismology, gravity, the strength of the shell, the
variation of latitude and the figure of the Moon. The chapter on tidal
friction is largely rewritten and what now seem to be the three most
reliable estimates of the true secular acceleration of the Moon agree in
suggesting that the provisional estimate in the last edition should be
considerably increased. The criticism of theories of continental drift,
convection and plate tectonics is much expanded. A new appendix
pinpoints directions for future geophysical research. The Earth
continues to provide a fundamental and comprehensive account of
geophysical problems, essential to all scientists concerned with
problems of the origin, history and physical constitution of the Earth.