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

[9] The Nebrodes mountains ¹ take their rise opposite ² to Aetna; they are not so lofty as Aetna, but extend over a much greater surface. The whole island is hollow under ground, and full of rivers and fire like the bed of the Tyrrhenian Sea, ³ as far as Cumaea, as we before described ⁴ For there are hot springs in many places in the island, some of which are saline, as those named Selinuntia ⁵ and the springs at Himera, while those at Aegesta ⁶ are fresh. Near to Acragas ⁷ there are certain lakes, ⁸ the waters of which taste like the sea, but their properties are very different, for if those who do not know how to swim plunge into them, they are not covered over by them, but float on the surface like pieces of wood.

The Palici ⁹ possess craters which cast up water in a jet, having the appearance of a dome, and then receive it back again into the same place it rose from. The cavern near Mataurum ¹⁰ has within it a considerable channel, with a river flowing through it under ground for a long distance, and afterwards emerging to the surface as does the El-Asi ¹¹ in Syria, which, after descending into the chasm between Apameia and Antioch, which they call Charybdis, rises again to the surface at the distance of about 40 stadia. Much the same circumstances are remarked of the Tigris ¹² in Mesopotamia, and the Nile in Africa, ¹³ a little before ¹⁴ its most notorious springs. The water in the neighbourhood of the city of Stymphalus, having passed under ground about 200 stadia, gives rise to the river Erasinus ¹⁵ in Argia; ¹⁶ and again, the waters which are ingulfed with a low roaring sound near Asea ¹⁷ in Arcadia, after a long course, spring forth with such copiousness as to form the Eurotas and the Alpheus, ¹⁸ whence has arisen a fable extensively credited, that if a certain charm is uttered over each of two crowns on their being cast into the stream where the two rivers flow in a common channel, each crown will make its appearance in its respective river according to the charm. As for what we might add with reference to the Timao, ¹⁹ it has already been particularized.