File:LongwallOld.png

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DescriptionLongwallOld.png	English: Original caption: "Fig. 24. -- Plan of individual roadway longwall mine." The three-compartment hoisting shaft is in the center of the central pillar, which is not mined in order to avoid subsidance around the hoist. The downdraft ventilation shaft is 100' left of the pillar. Arrows show directions of air flow. Access to the face is through roadways through the gob, protected by packwalls, and with the roof "brushed" to maintain clearance as the roof subsides.
Date	May 1921
Source	Coal Mining Methods in Missouri, School of Mines and Metallurgy Bulletin, Vol. 5, No. 4, University of Missouri, Rolla
Author	William Walbridge Weigel

Public domain	This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1929, and if not then due to lack of notice or renewal. See this page for further explanation.	United States
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	Date/Time	Thumbnail	Dimensions	User	Comment
current	15:15, 2 July 2009		738 × 1,000 (133 KB)	Douglas W. Jones (talk \| contribs)	{{Information \|Description={{en\|1=Original caption: "Fig. 24. -- Plan of individual roadway longwall mine." The three-compartment hoisting shaft is in the center of the central pillar, which is not mined in order to avoid subsidance around the hoist. T

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