Description of the Process of Manufacturing Coal Gas, for the Lighting of Streets Houses, and Public Buildings With Elevations, Sections, and Plans of the Most Improved Sorts of Apparatus Now Employed at the Gas Works in London and the Principal Provincial Towns of Great Britain; Accompanied With Comparative Estimates, Exhibiting the Most Economical Mode of Procuring This Species of LightPART III.Chapter 316 wordsPublic domainCLASSIFICATION OF PIT COAL, AND MAXIMUM QUANTITY OF GAS, OBTAINABLE FROM DIFFERENT KINDS OF COAL 41