Strabo Geography 6.2.9

[9] Over against Aetna rise the Nebrodes Mountains, ¹ which, though lower than Aetna , exceed it considerably in breadth. The whole island is hollow down beneath the ground, and full of streams and of fire, as is the case with the Tyrrhenian Sea , as far as the Cumaean country, as I have said before. ² At all events, the island has at many places springs of hot waters which spout up, of which those of Selinus and those of Himera are brackish, whereas those of Aegesta are potable. Near Acragas are lakes which, though they have the taste of seawater, are different in nature; for even people who cannot swim do not sink, but float on the surface like wood. The territory of the Palici has craters ³ that spout up water in a dome-like jet and receive it back again into the same recess. The cavern near Mataurus ⁴ contains an immense gallery through which a river flows invisible for a considerable distance, and then emerges to the surface, as is the case with the Orontes in Syria , ⁵ which sinks into the chasm (called Charybdis) between Apameia and Antiocheia and rises again forty stadia away. Similar, too, are the cases both of the Tigris ⁶ in Mesopotamia and of the Nile in Libya , only a short distance from their sources. And the water in the territory of Stymphalus ⁷ first flows underground for two hundred stadia and then issues forth in Argeia as the Erasinus River; and again, the water near the Arcadian Asea is first forced below the surface and then, much later, emerges as both the Eurotas and the Alpheius; and hence the belief in a certain fabulous utterance, that if two wreaths be dedicated separately to each of the two rivers and thrown into the common stream, each will reappear, in accordance with the dedication, in the appropriate river. And I have already mentioned what is told about the Timavus River. ⁸