A compact, collapsible and automatically expansible mining canvas is constructed and arranged so that a mine worker may stand under a supported roof section and extend into a newly sumped coal portion a forward section of a mining canvas so as to direct the air flow across the face of a newly mined coal section so as to remove any dangerous gasses and debris escaping therefrom. The mining canvas comprises an upper support and a lower support connected by pivotal intermediate support members and a canvas which is connected there between and which is preferably pleated so as to allow collapsible and expansible operation. Included in this invention is the method by which a miner may stand under an already supported section and extend to within a few feet of the newly mined or sumped face a compact, collapsed but expansible canvas section that is easily transportable to the face and which upon expansion will engage the roof and floor of the mine so as to direct the air flow against the face.