THIS is an important work on a subject which it is difficult to treat in systematic manner on account of the great complexity of the conditions involved. The variety of machines now made is almost overwhelming, and is continually increasing, while for the successful and intelligent design of machines of any one class the engineer must possess a faculty of invention, a sound judgment, some acquaintance with commercial conditions, familiarity with workshop processes, a knowledge of the many branches of applied mechanics and of physics, all the result of long study and practical experience. The treatment of so extensive a subject must of necessity be only partial, and the primary appeal of this book is to students of technical colleges. At the same time, the expert draughtsman will find much of interest and profit. The drawings are subordinate, and are introduced mainly to illustrate principles. The treatment is logical yet practical, very suggestive and germane to the subject, and the style is attractive and interesting. The writers can speak with authority, each having had experience as a professor of Sibley College, Cornell University, and also as a manager of an engineering works.
Elements of Machine Design.
By Dr. S. Kimball J. H. Barr. Pp. viii + 446. (New York: John Wiley and Sons; London: Chapman and Hall, Ltd., 1909.) Price 12s. 6d. net.