Some of the more interesting conclusions of a 1955 survey of atomic constants were the following. (1) Most familiar experiments described in general physics courses now carry negligible weight. (2) Probable errors in values of the constants are of the order of 10 ppm. (3) Use of x-ray “ experiments” has been a source of error in previous evaluations; theoretical interpretation of these results involves considerable uncertainty. (4) Electrochemical values of the Faraday are now in fair agreement, but their mean differs significantly from the value obtained by electromagnetic experiments. (5) There is still some evidence for variation of the velocity of light with frequency; however, the negative case appears stronger and is further strengthened by newer data.
Recent developments are discussed and the authors' analysis compared with the 1955 study of Cohen, DuMond, Layton, and Rollett. Recommended values for principal constants are given. These include a correction for an error in the Karplus and Kroll calculation of the anomalous moment of the electron, but do not reflect any experimental data reported since 1955.
