John Logie Baird and the Secret in the Box: The Undiscovered Story behind the World's First Public Demonstration of Television

Abstract

On January 26, 1926 (see Fig. 1), John Logie Baird gave a demonstration at his laboratory in 22 Frith Street, London, of the live transmission of moving images, obtained in reflected light with tonal graduation, to members of the Royal Institution. This event is generally accepted as the first public demonstration of true television [1], [2, pp. 88-107], [3, pp. 65-84]. Ten months earlier, on March 25, 1925, Baird had demonstrated the televising of moving silhouette images, at Selfridge's department store, on Oxford Street in London [2, p. 57], [3, p. 75]. What had changed in those ten months to enable Baird to televise a sufficient tonal range of moving human faces? This article describes the set of events which led up to Baird's accomplishment and answers the question concerning the technology employed.