With the creation of the BBC in 1922, wireless sets ceased to be obscure devices for military and commercial communication, and became household goods to entertain the British middle classes. Wireless amateurs, electrical engineers, inventors, and specialized physicists engaged in a cultural exchange among themselves and with the general public to explain and understand the mechanisms and possibilities of the new technology. This created a new arena for discussions on the existence of the ether at a time when highly esoteric physics (mainly relativity, but also quantum physics) had triggered a debate about its very existence. In this paper I explore the ways in which the ether saw its popularity renewed by its link to the modern wireless technologies. I argue that far from being part of an old, outdated physics, radio broadcasting was instrumental for the ether to remain popular, and even an element of modernity, among many wireless amateurs, engineers, and the general public in the 1920s and early 1930s.

One model, the resonance model, shaped scientific understanding of optical dispersion from the early 1870s to the 1920s, persisting across dramatic changes in physical conceptions of light and matter. I explore the ways in which the model was transmitted across these conceptual divides by analyzing the use of the model both in the development of theories of optical dispersion and in the interpretation of experimental data. Crucial to this analysis is the integration of the model into quantum theory because of the conceptual incompatibility between the model and quantum theory. What is more, a quantum understanding of optical dispersion set the grounds for the emergence of the first theories of quantum mechanics in 1925. A long-term history of the model’s transmission from the 1870s to the 1920s illuminates the ways in which the continuity of knowledge is possible across these discontinuities.