The New International Encyclopædia/Bituminous Shales

From Wikisource
Jump to navigation Jump to search

BITUMINOUS SHALES. Beds of shale occurring chiefly in the coal-measures, and containing such an amount of carbon and volatile matter that they are capable of being burned when mixed with but a little coal. They are indeed impure coal, with a large percentage of ash or earthy matter, which after burning retains the original form. See Coal.