Theoretical Astrophysics

SINCE the beginning of our present era, astro-nomy has been considered to be the foremost of exact sciences, and there can scarcely be any doubt that the idea of law and order in the linking of natural phenomena was first forced upon the dawning mind of man by the regular march of the stars. In the course of time, however, astronomical theory has been left behind by the rapidly increasing wealth of observational data to such an extent that present-day astronomy must largely be classified among the descriptive sciences, inspite of the triumphs of celestial mechanics and the arduous work done during the last fifteen years to raise theoretical astrophysics to the rank of a separate science. Astronomy is therefore more than ever a promising field for theoretical research, and Sir J. H. Jeans's book, which aims at summarising the present status of the young science, will undoubtedly provide inspiration to theoretical astrophysicists; at the same time it will encourage astronomers doing observational routine work to make enhanced efforts, and will disseminate the knowledge of modern astronomy among workers in allied sciences.

Astronomy and Cosmogony.

By Sir J. H. Jeans. Pp. x + 420 + 16 plates. (Cambridge: At the University Press, 1928.) 31s. 6d. net.