The pre-history of 20th century acoustics: the legacy of Lord Rayleigh

Abstract

Rayleigh's two-volume work “The Theory of Sound” was the crowning glory of 19th century acoustics, and it set the agenda for everything that followed in the 20th century. The talk will review Rayleigh's life and key contributions, which covered structural vibration as well as airborne acoustics. His interest in wave theory also extended to optics: he famously explained why the sky is blue. The talk will include images from the surviving laboratory at Terling Place, the ancestral home of the Rayleigh family. Apparatus associated with some of Rayleigh's iconic experiments in acoustics can still be seen there. A flight of stone steps in the grounds was an early inspiration for the theory of diffraction gratings, and this was followed up by an ultrasonic experiment involving a periodic array of muslin discs with variable spacing.