The interpretation of numerical results obtained by rigorous diffraction theory for cylinders and spheres

The classical solutions of the scattering problems for homogeneous spheres and circular cylinders are taken as the starting point for a physical discussion. The limiting cases arising if two or three of the parameters and are very small or very large are surveyed and interpreted. The remaining paper deals with bodies fairly large compared to the wavelength. It is shown that exact transformations and/or approximate theories may help in the problem of interpolating between rigorous results. It is also shown that the extinction by large bodies is due to a combination of the classical effects of diffraction and geometrical optics with the loss familiar edge effects and surface waves. The sign and magnitude of the edge effects for bodies of different refractive index admits of a simple explanation.