High-Frequency Scattering by an Impenetrable Sphere

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. As will be shown in Section VI, this treatment is also incomplete, for it does not apply to the backward half-space. A certain amount of confusion seems to exist in the literature concerning the application of Watson's transformation in the lit region.