（待翻译）A New Determination of Molecular Dimensions
The earliest determinations of the real sizes of molecules were made possible by the kinetic theory of gases, but thus far the physical phenomena observed in liquids have not helped in ascertaining molecular sizes. No doubt this is because it has not yet been possible to surmount the hurdles that impede the development of a detailed molecular-kinetic theory of liquids. It will be shown in this paper that the size of molecules of substances dissolved in an undissociated dilute solution can be determined from the internal viscosity of the solution and of the pure solvent, and from the diffusion rate of the solute within the solvent provided that the volume of a solute molecule is large compared to the volume of a solvent molecule. This is possible because, with respect to its mobility within the solvent and its effect on the viscosity of the latter, such a molecule will behave approximately like a solid body suspended in a solvent. Thus, in the immediate vicinity of a molecule, one can apply the equations of hydrodynamics to the motion of the solvent in which the liquid is treated as homogeneous and hence its molecular structure need not be taken into consideration. We will choose a sphere as the solid body that shall represent the solute molecules.