MARCHI

A. C. Cossor's history began in London in 1859, long before broadcasting, with thermometers, barometers and specialized glasswork. That experience made the move into electrical tubes natural: by 1902 the company had made an early cathode-ray tube. During the First World War it made R-type valves at its Highbury works. Continuity between technical glassmaking and valve manufacture is one of the brand's most distinctive features.

In 1922 Cossor introduced a valve designed in-house and established itself among British radio-component makers. Its valves went into receivers built by enthusiasts as well as those sold by the company. The Melody Maker kits, introduced in 1927, vividly represent that market: a listener could still build their own set. In 1930 Cossor sold its first complete receiver; its activities also extended into electronic instruments, including oscilloscopes.

The Highbury plant kept expanding until space ran out. The decision to open another works led to radio-cabinet production at Leyton from 1934. Cossor also followed the arrival of television: it advertised a receiver before regular British broadcasts began and showed a new one at the 1936 Radio Show. Cossor markings therefore point to a company that made valves, sets and instruments, along a path from scientific glassware to the new electronic media of the twentieth century.