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VOLpANIC VAPOURS.

discovered metals, to inflame instantly on theaccess of water, by which they are convertedinto earths or alkalies, offers an easy explana-tion of the origin of volcanic fires, could wesuppose that substances so extremely inflam-mable and oxydable have remained for agesin a metallic state. There may, however, beprocesses in the vast laboratory of the globethat constantly separate the earths from oxy-gen, and prepare them for the support of vol-canic fires, by which they are thrown uponthe surface, and a connection is establishedbetween the internal and external parts of theplanet.

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