It is very remarkable that fresh water should burst out close to the sea, as from pipes. But there is no end to the wonders that are connected with the nature of waters. Fresh water floats on sea water, no doubt from its being lighter; and therefore sea water, which is of a heavier nature642, supports better what floats upon it. And, in some places, different kinds of fresh water float upon each other; as that of the river which falls into the Fucinus; that of the Addua into the Larius; of the Ticinus into the Verbanus; of the Mincius into the Benacus; of the Ollius into the Sevinus; and of the Rhone into the Leman lake643 (this last being beyond the Alps, the others in Italy): all which rivers passing through the lakes for many miles, generally carry off no more water than they bring with them. The same thing is said to occur in the Orontes, a river of Syria, and in many others.

Some rivers, from a real hatred of the sea, pass under it, as does Arethusa, a fountain of Syracuse, in which the substances are found that are thrown into the Alpheus; which, after flowing by Olympia, is discharged into the sea, on the shore of the Peloponnesus644. The Lycus in Asia645, the Erasinus in Argolis, and the Tigris646 in Mesopotamia, sink into the earth and burst out again. Substances which are thrown into the fountain of Æsculapius at Athens647 are cast up at the fountain of Phalerum. The river which sinks into the ground in the plain of Atinum648 comes up again at the distance of twenty miles, and the Timavus does the same in Aquileia649.

In the lake Asphaltites, in Judæa, which produces bitumen, no substance will sink, nor in the lake Arethusa650, in the Greater Armenia: in this lake, although it contains nitre, fish are found. In the country of the Salentini, near the town of Manduria, there is a lake651 full to the brim, the waters of which are never diminished by what is taken out of it, nor increased by what is added. Wood, which is thrown into the river of the Cicones652, or into the lake Velinus in Picenum, becomes coated with a stony crust, while in the Surius, a river of Colchis, the whole substance becomes as hard as stone. In the same manner, in the Silarus653, beyond Surrentum, not only twigs which are immersed in it, but likewise leaves are petrified; the water at the same time being proper for drinking. In the stream which runs from the marsh of Reate654 there is a rock, which continues to increase in size, and in the Red Sea olive-trees and green shrubs are produced655.

There are many springs which are remarkable for their warmth. This is the case even among the ridges of the Alps656, and in the sea itself, between Italy and Ænaria, as in the bay of Baiæ, and in the Liris and many other rivers657. There are many places in which fresh water may be procured from the sea, as at the Chelidonian Isles, and at Arados, and in the ocean at Gades. Green plants are produced in the warm springs of Padua, frogs in those of Pisa, and fish in those of Vetulonia in Etruria, which is not far from the sea. In Casinas there is a cold river called Scatebra, which in summer is more full of water658. In this, as in the river Stymphalis, in Arcadia, small water-mice are produced. The fountain of Jupiter in Dodona, although it is as cold as ice, and extinguishes torches that are plunged into it, yet, if they be brought near it, it kindles them again659. This spring always becomes dry at noon, from which circumstance it is called Ἀναπαυόμενον660: it then increases and becomes full at midnight, after which it again visibly decreases. In Illyricum there is a cold spring, over which if garments are spread they take fire. The pool of Jupiter Ammon, which is cold during the day, is warm during the night661. In the country of the Troglodytæ662, what they call the Fountain of the Sun, about noon is fresh and very cold; it then gradually grows warm, and, at midnight, becomes hot and saline663.

In the middle of the day, during summer, the source of the Po, as if reposing itself, is always dry664. In the island of Tenedos there is a spring, which, after the summer solstice, is full of water, from the third hour of the night to the sixth665. The fountain Inopus, in the island of Delos, decreases and increases in the same manner as the Nile, and also at the same periods666. There is a small island in the sea, opposite to the river Timavus, containing warm springs, which increase and decrease at the same time with the tides of the sea667. In the territory of Pitinum, on the other side of the Apennines, the river Novanus, which during the solstice is quite a torrent, is dry in the winter668.

In Faliscum, all the water which the oxen drink turns them white; in Bœotia, the river Melas turns the sheep black; the Cephissus, which flows out of a lake of the same name, turns them white669; again, the Peneus turns them black, and the Xanthus, near Ilium, makes them red, whence the river derives its name670. In Pontus, the river Astaces waters certain plains, where the mares give black milk, which the people use in diet. In Reate there is a spring called Neminia, which rises up sometimes in one place and sometimes in another, and in this way indicates a change in the produce of the earth671. There is a spring in the harbour of Brundisium that yields water which never becomes putrid at sea. The water of the Lyncestis, which is said to be acidulous, intoxicates like wine672; this is the case also in Paphlagonia673 and in the territory of Calenum674. In the island of Andros, at the temple of Father Bacchus, we are assured by Mucianus, who was thrice consul, that there is a spring, which, on the nones of January, always has the flavour of wine; it is called Διὸς Θεοδοσία675. Near Nonacris, in Arcadia, the Styx676, which is not unlike it either in odour or in colour, instantly destroys those who drink it. Also in Librosus, a hill in the country of the Tauri, there are three springs which inevitably produce death, but without pain. In the territory of the Carrinenses in Spain677, two springs burst out close together, the one of which absorbs everything, the other throws them out. In the same country there is another spring, which gives to all the fish the appearance of gold, although, when out of the water, they do not differ in any respect from other fish. In the territory of Como, near the Larian lake, there is a copious spring, which always swells up and subsides again every hour678. In the island of Cydonea679, before Lesbos, there is a warm fountain, which flows only during the spring season. The lake Sinnaus680, in Asia, is impregnated with wormwood, which grows about it. At Colophon, in the cave of the Clarian Apollo, there is a pool, by the drinking of which a power is acquired of uttering wonderful oracles; but the lives of those who drink of it are shortened681. In our own times, during the last years of Nero’s life, we have seen rivers flowing backwards, as I have stated in my history of his times682.

And indeed who can be mistaken as to the fact, that all springs are colder in summer than in winter683, as well as these other wonderful operations of nature; that copper and lead sink when in a mass, but float when spread out684; and of things that are equally heavy, some will sink to the bottom, while others will remain on the surface685; that heavy bodies are more easily moved in water686; that a stone from Scyros, although very large, will float, while the same, when broken into small pieces, sinks687; that the body of an animal, newly deprived of life, sinks, but that, when it is swelled out, it floats688; that empty vessels are drawn out of the water with no more ease than those that are full689; that rain-water is more useful for salt-pits than other kinds of water690; that salt cannot be made, unless it is mixed with fresh water691; that salt water freezes with more difficulty692, and is more readily heated693; that the sea is warmer in winter694 and more salt in the autumn695; that everything is soothed by oil, and that this is the reason why divers send out small quantities of it from their mouths, because it smoothes any part which is rough696 and transmits the light to them; that snow never falls in the deep part of the sea697; that although water generally has a tendency downwards, fountains rise up698, and that this is the case even at the foot of Ætna699, burning as it does, so as to force out the sand like a ball of flame to the distance of 150 miles?