| Description | Reports on visits of representatives of Doncaster Amalgamated Collieries Limited to America, Holland and Germany, especially the Ruhr, to study mining techniques, including detailed report on ower stowing and other mechanical devices, 1945 - 1946.
Reports on visits to local collieries (Clipstone, Lofthouse, Askern Main, Frickley, Wemyss Coal Co) to inspect mechanical methods, 1941 - 1945. |