The Rule-Making Authority in the English Supreme Court, by Samuel Rosenbaum. Boston, The Boston Book Co., 1917, pp. xiv, 321. This volume is the fourth in the University of Pennsylvania Law School Series, and is the work of a fellow of that school during the years 1913-1915. In common with the other books of the series, its object is to aid the scientific study of legal problems and to help to improve the law. No subject, surely, is more worthy of presentation to American readers than this, and none is more full of important suggestions for the improvement of our practice.