This volume constitutes a radical revision and extension of the author’s 1938 Tables. Herein is an extensive table of normal probability functions. 3-point interpolation coefficients are given with 4 figure arguments. These coefficients are compensatorily rounded off to five figures. A similar rounding off to seven figures of 4-point coefficients has been made. Truman Kelley’s method for normalizing variance ratios, which he presents together with tables facilitating the process, is of particular importance for experimental scientists.