Caption:

One of four bakelite office telephones for inter-office communication, manufactured by ATM. Phenol formaldehyde, better known by its trade name 'Bakelite', formed a useful mouldable plastic, with very good electrical insulating properties. Named after its inventor, Leo Baekeland, it was the first plastic to be used for making radios, and was ideal for the Art Deco-style designs of the 1920s and 1930s.