DISCUSSION. ON DIFFERENT METHODS OF WORKING COAL, AND ON COAL MINING IN DEEP WORKINGS

G R STEPHENSON, J KNOWLES, E BAINBRIDGE
1870 Minutes of the Proceedings of the Institution of Civil Engineers  
doi:10.1680/imotp.1870.23028 fatcat:x2ob4fbzdzacpixwnoq7pjf7ne