00967cam a22002531  4500001001300000003000400013005001700017008004100034010001700075035001800092040002300110042001200133050002000145110003900165245020500204250002000409260004800429300002200477500006400499650004200563650004400605650003300649650003100682gs 38000127 DLC20260227111343.0740129s1938    dcu           000 0 eng    ags 38000127   a(OCoLC)785160  aDLCcNdOCoLCdDLC  apremarc00aTN23b.U75 19381 aUnited States.bGeological survey.10aOperating regulations to govern coal-mining methods and the safety and welfare of minersbon leased lands on the public domain under the act of February 25, 1920 (41 Stat. 437) and amendments thereto.  aSecond edition.  aWashington,bU.S. Govt. print. off.,c1938.  aii, 46 p.c23 cm.  aAt head of title: United States Department of the interior. 0aCoal mines and miningzUnited States. 0aCoal mines and miningxSafety measures. 0aPublic landszUnited States. 0aMining lawzUnited States.