XXV
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Some waters are fatal, although they give no indication of this either by smell or taste. In Arcadia, near Nonacris, the river called by the people there the Styx lures strangers to ruin, as its appearance and smell rouse no suspicion. This is like the drugs of accomplished poisoners, which cannot be detected save by their fatal effects. The water I mentioned a little above brings destruction with amazing swiftness, and allows no opportunity of applying a remedy. It hardens immediately it is drunk, and, much like chalk under the influence of water, it sets and binds fast the bowels. There is a poisonous water in Thessaly, near Tempe, shunned by all cattle and wild beasts. It comes out through seams of iron and copper, and contains the power of softening the very hardest material. It does not nourish any trees either, and it kills grass. Certain rivers possess a peculiar and strange power. Some there are whose draught dyes whole flocks of sheep. Within a short time those that were black have white fleeces; in other cases those that came white go away black. This is what two rivers in Boeotia do, one of which from its effect is called Melas (Blackwater). Both the rivers issue from the same lake, to go on their opposite missions. So, too, in Macedonia, Theophrastus asserts there is a river to which shepherds who desire to turn their sheep white bring them. If the sheep drink it for any length of time, their colour changes as if they had been dyed. But if those people want a dark wool, they have a dyer ready at hand who charges nothing; they have merely to drive the same flock to the river Peneus. I have recent authorities for the statement that there is a river in Galatia that has the same power of changing the colour in all animals, while in Cappadocia there is one which if drunk changes the colour of horses but not of any other animal; their skin is dappled with white spots.
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It is well known that there are lakes whose waters bear up those who cannot swim. There used to be a pool in Sicily, there still is one in Syria, in which brickbats float, and no objects thrown in, however heavy, will sink. The cause of it is obvious. Weigh any object and compare it with water while they are equal bulk for bulk. If the water is the heavier, it will bear the object that is lighter than itself, and will raise it above its surface to a height proportionate to its lightness; objects heavier than the water will sink in it. But if the weight of water and of the object compared with it in respect of weight be equal, the object will neither go to the bottom nor yet will it stick up; it will just be in equipoise with the water. It will float, it is true, but almost submerged and without any part projecting. The differences in weight give the reason why some logs float almost entirely above water, while some sink to their centre, and some go down until they are in equipoise with the water. For it always holds good that, when the weights of the two are equal, neither yields to the other; but objects heavier than water sink, those lighter are upborne.
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Now heavy and light do not refer to our judgment of weight, but are relative to the medium by which an object is to be supported. So when water is heavier than the human body or than a stone, it does not allow the inferior weight to sink. So it comes to pass that in some lakes even stones will not go to the bottom; I mean hard solid stones. There are many light pumice stones, of which in Lydia whole islands that float are composed. Theophrastus is my authority for the statement. I have myself seen a floating island in the lake near Cutiliae. Another is carried about in the Vadimonian Lake, another in the lake by Statonia. The island at Cutiliae contains trees and grows grass, and yet it is borne up by the water, and is wafted now in this direction, now in that, not merely by wind, but even by a mere air. So light the breath that moves it that night and day it never remains stationary in one spot. There are two reasons for it: first, there is the weight of the water, which is medicated and therefore heavy; and then there is the portable material of the island itself, which contains no solid body, although it supports trees. Perhaps in the first instance the thick liquid laid hold upon and made fast light trunks and boughs scattered over the surface of the lake. So also whatever rocks are in the island, you will find porous and hollow. They resemble those formed of moisture that has hardened especially near the banks of medicinal springs; in such cases the scourings of the spring coalesce and the foam is solidified. It is necessarily light, being formed by concretions of windy, empty material.
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There are other peculiarities attaching to waters of different kinds, of which no explanation can be offered. For example, why should Nile water make women more fruitful? So effective is it in this respect that in some instances wombs shut up in prolonged barrenness have relaxed so as to render conception possible. Or why should certain waters in Lycia prevent miscarriage, being sought after by ladies who are subject to this frailty? For my own part I set these down among vulgar errors. It is firmly believed by people that certain waters, whether applied outwardly or taken inwardly, affect the body with scab, certain with leprosy and foul blotches over the skin. Water gathered from dew, they say, has this fault. Wouldn’t any one suppose that water that turns into ice is the heaviest of all? The truth is just the opposite of this. The change takes place in the thinnest water, which for that very reason is most easily congealed by the cold. The origin of the stone that resembles ice is plain from the very name used for it by the Greeks. They apply the term crystal (κρύσταλλος) equally to the transparent stone and to the ice from which the stone is supposed to be formed. Rain water, which contains very little solid matter, once it is frozen becomes more and more condensed through the persistence of the longer cold until all the air is expelled, and it is compressed to the last degree; then what was once moisture is changed into stone.