Title: A Rudimentary Treatise on Coal and Coal Mining
Description: Book digitized by Google from the library of the University of Wisconsin - Madison and uploaded to the Internet Archive by user tpb.
Subjects: coal, feet, seams, coalfield, coalfields, thickness, whilst, strata, colliery, shaft, south wales, total thickness, cubic feet, square miles, feet thick, lower seams, inches diameter, working face, public domain, main haulage