Coal Face (1935) was the first influential film to be made by the GPO Film Unit. It continued the experimentation with sound effects and music first initiated in Song of Ceylon (d. Basil Wright, 1934) and Pett and Pott (d. Alberto Cavalcanti, 1934), and was described in the Film Society programme of 27 October 1935 as "an experiment in sound". What links these three films is th...