Bk XV:307-360 Pythagoras's Teachings: Physical changes.
"Though many instances, I have heard and known of, come to mind, I shall relate only a few more. Does not water, also, offer and receive new forms? Your stream, horned Ammon, is chill at mid-day, and warm in the morning and evening, and they tell of the Athamanians setting fire to wood, by pouring your waters over it, when the moon wanes to her smallest crescent.
The Cicones have a river, whose waters when drunk turn the vital organs to stone, and that change things to marble when touched. The Crathis, and the Sybaris, here, near our own country, make hair like amber or gold: and what is more amazing, there are streams that have power to change not merely the body but the mind as well. Who has not heard of the disgusting waves of Salmacis, and the Aethiopian lakes? Whoever wets his throat with these, is either maddened, or falls into a strange, deep sleep.
Whoever slakes his thirst at Clitor's fountain, shuns wine, and only enjoys pure water, whether it is due to a power in the water that counteracts hot wine, or whether, as the natives claim, Melampus, Amythaon's son, when he had saved the demented daughters of Proetus from madness, by herbs and incantations, threw the remnants, of what had purged their minds, into its springs, and the antipathy to wine was left behind in its waters. The flow of the River Lyncestius has the opposite effect, so that whoever drinks even moderately of it, stumbles about, as if they had drunk pure wine. There is a place in Arcadia, the ancients called Pheneus, mistrusted for its dual-natured waters: beware of them at night, drunk at night they are harmful: in the day they can be drunk without harm. So, rivers and lakes can harbour some power or other.
There was a time when Ortygia floated on the waves, now it is fixed, and the Argo's crew feared the Symphlegades' collisions, and the spray of their crashing waves, islands that now stand there motionless, and resist the winds.
And Aetna that glows, with its sulphurous furnaces, was not always on fire, and will not always be on fire. For if the earth is a creature, that lives, and, in many places, has vents that breathe out flame, she can alter her air passages, and as frequently as she shifts, she can close these caverns and open others. Or, if swift winds are confined in the deep caves, and strike rock against rock, or against material containing the seeds of fire, and Aetna catches alight from the friction, the caves will be left cold when the wind dies. Or, if it is bituminous substances that take fire, and yellow sulphur, burning with little smoke, then, when the ground no longer provides rich fuel, or nourishment for the flames, and their strength fails after long centuries, earth herself will lack the support of devouring nature, and will not withstand that famine, and forsaken, will forsake her fires.
There is a tale of men in Hyperborean Pallene, who are used to clothing their bodies in soft plumage, by plunging nine times in Minerva's pool: for my part, I can scarcely believe it: also the women of Scythia are said to practise the same arts, sprinkling their bodies with magic liquids."