01442cam a22003011  4500001001300000003000400013005001700017008004100034010001700075035001900092040001900111042001200130050002100142110003700163245041000200260007700610300001800687490004100705500012400746650002000870650002000890700003000910700004600940700003400986700003001020810007301050999001701123gs 35000001 DLC20260227111339.0790607s1934    ilua         s000 0 eng    ags 35000001   a(OCoLC)5045725  aDLCcTxCMdDLC  apremarc00aTP325b.I63 19342 aIllinois State Geological Survey10aContributions to the study of coal:bA proposed simplification of the Parr unit coal formula,cby Gilbert Thiessen. Ash-to-mineral matter correction in coal analyses, by Gilbert Thiessen. Unit coal as a basis of coal standardization as applied to Illinois coals, by G. H. Cady and O. W. Rees. Studies of the graphical method of calculating pure coal calorific value, by Gilbert Thiessen and Frank H. Reed.  aUrbana, Illinois,bPrinted by authority of the state of Illinois,c1934.  a99 p.billus.1 aIts Report of investigationsvno. 32  aAt head of title: State of Illinois. Department of Registration and Education. Division of the State Geological Survey. 0aCoalxAnalysis. 0aCoalzIllinois.1 aThiessen, Gilbert,d1905-1 aCady, Gilbert H.q(Gilbert Haven),d1882-1 aRees, Orin Wainwright,d1898-1 aReed, Frank Hynes,d1890-2 aIllinois State Geological Survey.tReport of investigationsvno. 32.  c27157d27157