A-Dependence of Nuclear Charge and Mass Distributions

A discussion is given of the $A$ dependence of the root-mean-square radii of the nuclear charge and mass distributions both along and at right angles to the valley of maximum stability. In the second case, i.e., for isotopes and isotones, it is pointed out that the charge radii never obey an $A^{\frac{1}{3}}$ dependence even approximately, but that for mass radii the experimental evidence is not in conflict with such a dependence. Attention is also drawn to the differences between the distribution of proton centers and the charge distribution.