c. 1220-1282

Italian scholar who put forth ideas of varying accuracy concerning geology. Ristoro maintained that mountains are formed because the stars pull earth upward, a notion later reflected in the Divine Comedy of Dante Alighieri. On the other hand, Ristoro was quite correct in stating that the Earth's interior is in a molten state. Near the end of his life, he found jumbles of rock and gravel in the Alps—a geological disturbance possibly created during the end of the last Ice Age—that he cited as evidence of the biblical flood.