HISTORY
Baird was giving regular demonstrations at 22 Frith Street at this time. The Westminster Gazette reported: ‘From a Soho room yesterday a Westminster Gazette representative saw the likeness of a man’s face transmitted by wireless to a neighbouring room. … Mr. Baird has spent two years working continuously upon his invention. “Consequently,” he said, with an apologetic smile, as he surveyed his laboratory “I have had to be economical with my materials. A ‘junk’ merchant would probably give me £5 for the lot”.’ Welcome Visitors at 22 Frith Baird would recall: ‘I continued to work away in my Frith Street attic transmitting crude outlines of letters and figures anxiously watching the cash getting less and less. One day I had two visitors. One was Mr. Gordon Selfridge, junior, the other had visited me in Hastings and was interested in my work. He had mentioned it to Selfridge and Selfridge, who was on the lookout for an attraction for his [the store’s] Birthday Week celebrations, had thought that television would be a startling exhibit.’ The visitor who had visited Baird’s laboratory in Hastings was Count Anthony Herbert de Bosdari, who was a friend of Gordon Selfridge junior. They had both attended Winchester College, and Bosdari had been working in Selfridges marketing department. Bosdari thus deserves credit as the go-between who occasioned the Selfridges demonstrations. He was the son of the Italian banker Count Maurizio de
The television ‘camera’ apparatus used a double-8 interlaced lens configuration, in other words, 16 lenses in total fitted close to the outside edge of the disc broken into two 8-lens semi-spirals, not a single spiral as erroneously interpreted in Davis’ drawing entitled ‘The Lens Disc’ above. The actual lens configuration’s use in the apparatus has been correctly described in numerous other historical sources and in considerable detail by Don McLean in his recent article. The description in the Illustrated London News also included a description of the receiver apparatus: This pulsating current is then transmitted through space to the receiving station, where it is amplified for controlling a lamp whose light, passing through the lenses of another revolving disc, impinges upon a ground-glass screen on which the image is reproduced by a series of fine strips of varying shades. However crude the results of the present experiments may seem, it must not be forgotten that the early experiments in wireless signalling were of a very simple nature, notably that of Hertz, who discovered that an electric spark discharged at one end of a room caused his ‘resonator’ to respond at the other end. Crucially, the apparatus demonstrated in early 1925 and at Selfridges was divided into two sections, as in Baird’s account in Wireless World, as illustrated in the Davis drawings, in the Illustrated London News just above, and in other accounts (to be discussed). This would have removed any doubts that the pictures were travelling via wireless.
an application of the Becquerel effect. A.E. Becquerel had observed the photovoltaic effect for the first time in 1839 by detecting small currents when silver chloride was illuminated. Baird was experimenting concurrently with different types of cells, and Thalofide may have been tried as far back as June 1924. Burns was first to suggest that such a cell may have been the one that helped make possible the first true television images in October of 1925 and subsequently used for the first public demonstration of television in January 1926. However it is reasonable to conclude, from Baird’s own accounts and from the Davis drawing, that a colloidal cell was used by Baird for the Selfridges demonstrations. Another detailed written account of the apparatus Baird was using during the time just before the Selfridges demonstrations can be found in The Illustrated London News of 14 March 1925. In his [Baird’s] recent experiments, the transmission was from one room to another but as the sending and receiving instruments were entirely separate, with transmission entirely by radio, longer ranges may be possible with radio waves of greater power. The instruments are rough and purely experimental at present, but they have demonstrated the possibility of actually seeing the representation of a living object by radio. The human face appears only as a blurred white oval with dark patches for the eyes and mouth but it is possible to note, on the ground-glass screen of the receiver, the effect of eye-winking and opening the mouth by the person at the transmitting end. Most of the apparatus has been constructed of makeshift materials—improvised wireless gear not really suitable for the purpose, and even a number of lenses from bicycle lamps. The next stage in development of the system will be the construction of properly built instruments to overcome the flickering indistinctiveness and lack of detail inherent in the experimental receiving machine. In the Baird system of television, light is projected onto a sensitive cell through a system of lenses fitted to a disc that revolves at five hundred revolutions per minute. The light next becomes interrupted by passing through a serrated disc turning five thousand revolutions per minute, and then falls on a colloidal cell invented by Mr. Baird, and is converted into a current of varying intensity.
Baird’s receiving apparatus in 22 Frith Street, 4 Mar 1925. Note the triangular viewing tunnel and the large Nipkow disc, made of thick cardboard, and punched with 16 rectangular holes. In the foreground is a radio aerial. The three valves are for amplifying the synchronisation signal from the transmitter apparatus. Image source: Royal Television Society, Westminster Gazette
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SEPTEMBER 2025 Volume 47 No.3
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