Post Office 332 telephone, 1938.

Man checking an automatic telephone exchange, 1933.

Post Office 706 telephone, c 1959.

'School telephone' in polished wood case, 1921-1940.

'School telephone' in polished wood case, 1921-1940.

'School telephone' in polished wood case, 1921-1940.

Telephone exchange operators in gas masks, 31 October 1938.

Gower-Bell telephone, 1881.

Gower-Bell telephone, 1881.

Crosley table telephone, 1879.

Crosley table telephone, 1879.

Bell's centennial telephone transmitter, 1876.