THIS is the second edition of an American book, the first of which was reviewed in NATURE of July 31, 1937. It is an exceedingly lucid and simply written students' text-book, that should prove useful to engineers or physicists commencing the study of aeronautics. A feature of the book is the large number of worked examples in the text, and further exercises at the end of each chapter. These are carefully graded and form an admirable addition to the book; one which might well be added to most English books on this subject of the same standard.
Elements of Practical Aerodynamics
By Prof. Bradley Jones. Second edition. Pp. viii + 436. (New York: John Wiley and Sons, Inc.; London: Chapman & Hall, Ltd., 1939.) 18s. 6d. net.