Note on the whispering gallery of St Paul's Cathedral, London
A E Bate · Proceedings of the Physical Society · 1938
The apparent disagreement between Rayleigh's deduction and those of Raman concerning the whispering-gallery phenomenon is shown to depend on the fact that Raman used a sustained source which gave rise to interference, whereas Rayleigh dealt with a whisper projected in one direction. Further, it is shown that, whereas Rayleigh attributed the success with a whisper to the fact that it is composed of high frequencies, low frequencies are projected equally well, and that actually the success attained with a whisper is due to its low intensity, which does not give rise to audible echoes. Explanations are offered of the circumferential and radial alternations of sound mentioned by Raman and Sutherland.