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GENESIS THE MIRACLES AND THE PREDICTIONS ACCORDING TO SPIRITISM > GENESIS > CHAPTER VII - GEOLOGICAL OUTLINE OF THE EARTH > DELUGE PERIOD > 44
44. A no less characteristic fact, and one the cause of which is not yet explained, is that among the diluvial rocks are found the first aerolites. It is, then, at this epoch that they began to form. The cause which produced them did not previously exist.