(I.) The Theory of Measurements. By L. Tuttle and J. Satterly. Pp. xi+333. 12s. 6d. net. 1925. (Longmans, Green & Co.) - (II) A First Course in Statistical Method. By G. I. Gavett. Pp. viii+358. 17s. 6d. 1925. (M’Graw-Hill Book Co.)