Abstract Instalment Mathematics Handbook: With Working Formulas for All Types of Transactions. Milan V. Ayres (Consulting Statistician, 5401 Woodlawn Ave., Chicago 15, Ill.). New York 10: Ronald Press (15 East 26th St.), 1946. Pp. xvi, 267. $10.00. Reviewed by Carl H. Fischer Mathematical Tables and Other Aids to Computation. Published quarterly beginning January 1943 by the National Research Council. (Number 15, July 1946 was the last issue available at the time of writing this review.) Beginning with 1947 the subscription price for each calendar year is $4.00, payable in advance; ordinary single numbers, $1.25. Earlier ordinary single numbers, each $1.00, and all numbers for each of the years 1943 to 1946 inclusive, $3.00. Special single number 7, Guide to Tables of Bessel Functions, $1.75, and number 12, $1.50. All payments are to be made to National Academy of Sciences, 2101 Constitution Avenue, Washington, D. C. Edited on behalf of the Committee on Mathematical Tables and Other Aids to Computation by Raymond Clare Archibald (Professor Emeritus, Brown University) and Derrick Henry Lehmer with the cooperation of Leslie John Comrie and Solomon Achillovich Joffe. Reviewed by Kenneth J. Arnold Industrial Experimentation [Revised Edition]. K. A. Brownlee (Research Department, Distillers Co., Ltd., Great Burgh, Epsom, Surrey, England). A revision of the 1945 memorandum of same title reviewed in this JOURNAL, March 1946. Directorate of Ordnance Factories (Explosives), Ministry of Supply. London, W.C. 2: H. M. Stationery Office, 1946. Pp. 116. 2s. Paper. (New York 20: British Information Services (30 Rockefeller Plaza), 1946. $0.60.) Two reviews follow: Reviewed by George W. Brown Measuring Business Cycles. Arthur F. Burns (Director of Research; Professor of Economics) and Wesley C. Mitchell (Director of Research, 1920–1946; Professor Emeritus of Economics). (National Bureau of Economic Research; Columbia University). Studies in Business Cycles, No. 2. New York 23: National Bureau of Economic Research, Inc. (1819 Broadway), 1946. Pp. xxvii, 560. 85.00. Reviewed by Elmer C. Bratt How to Read Statistics. R. L. C. Butsch (Formerly Professor of Education, Marquette University). Milwaukee 1, Wis.: Bruce Publishing Co. (524–544 N. Milwaukee St.), 1946. Pp. v, 184. $2.50. Two reviews follow: Reviewed by Louis Guttman, Helen M. Walker Rudimentary Mathematics for Economists and Statisticians. W. L. Crum (Professor of Economics) and Joseph A. Schumpeter (Professor of Economics). (Harvard University.) A revision of Supplement to Quarterly Journal of Economics, Vol. 52, May 1938. New York 18: McGraw-Hill Book Co., Inc. (330 West 42nd St.), 1946. Pp. xi, 183. $2.50. Two reviews follow: Reviewed by J. E. Morton, Gerhard Tintner On the Solution of Normal Equations and Related Topics. David B. Duncan (Pawlett Scholar, University of Sydney) and John F. Kenney (University of Wisconsin at Milwaukee). Milwaukee 3, Wis.: Book Store, University Extension Division (623 West State St.), 1946. Pp. iii, 35. $1.00. Paper. Reviewed by Walter L. Deemer, Jr. Government Statistics for Business Use. Edited by Philip M. Hauser (Assistant Director, Bureau of the Census) and William R. Leonard (Deputy Chief, Division of Statistical Standards, Bureau of the Budget). (Washington, D. C.) New York 16: John Wiley & Sons, Inc. (440 Fourth Ave.), 1946. Pp. xvi, 432. $8.00. Reviewed by William A. Spurr Changes in Income Distribution During the Great Depression. Horst Mendershausen (Professor of Economics, Bennington College). Conference on Research in Income and Wealth, Studies in Income and Wealth, Vol. 7. New York 23: National Bureau of Economic Research, Inc. (1819 Broadway), 1946. Pp. xviii, 168. $2.50. Two reviews follow: Reviewed by Morris H. Hansen, John Lintner Five Week Patterns of Prices and Volume: A Classification of the Weekly Movements of Trading Velocity and the Dow Jones Industrial Averages through the Twenty Year Period 1926–1945. Arthur A. Merrill. Schenectady 8, N. Y.: the Author (1567 Kingston Ave.), 1946. Pp. ii, 32. $1.00. Paper. Reviewed by Owen Ely