§23.20Διὰ τί τὸ ἁλμυρὸν ὕδωρ οὐκ ἀπόρρυτόν ἐστιν;
Why is salty water not flowing?
ἢ διότι τὸ μὲν βαρὺ στάσιμον; τὸ δὲ ἁλμυρὸν βαρύ· διὸ καὶ τὰ θερμὰ μόνα τῶν ἁλμυρῶν ὑδάτων ἀπόρρυτά ἐστιν.
Is it because that which is heavy is stationary, and salty water is heavy; wherefore also only the warm of salty waters are flowing.
ἔχει γὰρ κουφότητα ἐν αὑτοῖς, ἥ κρατεῖ τῆς κατὰ τὴν ἁλμυρίδα βαρύτητος· τὸ γὰρ θερμὸν κουφότερόν ἐστιν.
For they have lightness in themselves, which prevails over the heaviness due to the saltiness; for that which is hot is lighter.
ἔτι τὰ μὲν ἀπόρρυτα διηθεῖται διὰ τῆς γῆς· ἠθουμένων δὲ ἀεὶ μάλιστα ὑφίσταται τὸ παχύτατον καὶ βαρύτατον, ἐκκρίνεται δὲ τὸ κοῦφον καὶ καθαρόν· ἔστι γὰρ τὸ μὲν ἁλμυρὸν βαρύ, τὸ δὲ γλυκὺ κοῦφον.
Furthermore, flowing waters are filtered through the earth; and when they are filtered, the densest and heaviest always settles most, while the light and pure is separated out; for salty water is heavy, and sweet water is light.
διόπερ ἐστὶ γλυκέα τὰ ἀπόρρυτα.
Therefore flowing waters are sweet.
τὸ δ’ αὐτὸ αἴτιόν ἐστι καὶ διὰ τί τὸ ἁλμυρὸν ὕδωρ κινούμενον καὶ μεταβάλλον γλυκύτερον γίνεται· κουφότερον γὰρ καὶ ἀσθενέστερον διὰ τὴν κίνησιν γίνεται.
And the same is the cause also why salty water, when moved and changing, becomes sweeter; for it becomes lighter and weaker through the movement.
§23.21Διὰ τί ἐν τῇ Λιβύῃ ἐὰν ὀρύξῃ τις παρὰ τὴν θάλατταν, τὸ πρῶτον πότιμον, εἶθ’ ἁλμυρὸν γίνεται ταχύ, ἐν δὲ τοῖς ἄλλοις τόποις ἧττον ποιεῖ τοῦτο;
Why in Libya, if one digs near the sea, is the water at first drinkable, and then quickly becomes salty, whereas in other places this happens less?
πότερον ὅτι τὸ μὲν πρῶτον τὸ ὑπάρχον ὕδωρ ἐν τῷ τόπῳ καὶ τὸ πεπεμμένον ὑπὸ τῆς γῆς ἐστιν, ὅταν δὲ χρονισθῇ, ἡ θάλαττα προσδιηθουμένῃ διὰ τὸ πρόσφατον εἶναι ποιεῖ ἁλμυρώτερον;
Is it because the first water is that which was already present in the place and concocted by the earth, but when time passes, the sea, by filtering through additionally, makes it saltier because of its being fresh?
ἐν δὲ τοῖς ἄλλοις ἢ οὐκ ἔχει ἢ πολὺ ὕδωρ διὰ τὸ μὴ ξηραίνεσθαι τὸν τόπον.
And in other places, either it does not have this, or there is much water because the place is not dried up.
§23.22Διὰ τί τοὺς ἅλας θᾶττον τήκει τὸ ἁλμυρὸν ὕδωρ ἢ τὸ πότιμον;
Why does salty water dissolve salt faster than drinkable water?
ἢ διότι τὸ μὲν τήκεσθαί ἐστι τὸ ὑπὸ τοῦ ὑγροῦ ἢ θερμοῦ εἰσιόντος διαιρεῖσθαι, ὥστε ὑγρὸν εἶναι;
Or is it because to be dissolved is to be divided by the entering moisture or heat, so as to become liquid?
οὐ τήκει δὲ ἢ τὰ ὅλως μὴ δυνάμενα εἰσιέναι, ἢ τὰ οὕτως ὥστε μὴ θιγγάνειν.
And it does not dissolve either those things which are completely unable to enter, or those which enter in such a way as not to touch.
μόλις δὲ τήκει τὰ ῥᾳδίως διεξιόντα· τὰ δ’ ἐπιόντα βιαζόμενα, ταῦτα τάχιστα διαιρεῖ.
And it scarcely dissolves those which pass through easily; but those which attack by forcing their way, these it divides most quickly.
οὐκ εἰσέρχεται δὲ τὰ λίαν μεγαλομερῆ· ὑπερέχει γὰρ τῶν πόρων. τὰ δὲ μικρομερέστερα διέρχεται οὐ ψαυόμενα.
Now things that are too large in their parts do not enter, for they exceed the size of the pores; while those with smaller parts pass through without touching.
ἔστι δὲ τὸ μὲν πότιμον λεπτόν, τὸ δὲ ἁλμυρὸν παχύτερον, ὥστε τὸ μὲν ῥᾳδίως διὰ λεπτότητα διαδῦνον μόλις τήκει, τὸ δὲ εἰσέρχεται μέν, ἧττον δὲ διὰ τὸ μεγαλομερέστερον εἶναι διαιρεῖ, καὶ βιάζεται θᾶττον.
Now drinkable water is thin, and salty water is denser, so that while the former, slipping through easily due to its thinness, scarcely dissolves, the latter enters indeed, but divides less because of having larger parts, and forces its way faster.
§23.23Διὰ τί τὸ ὕδωρ ἧττον φαίνεται λευκόν, ἐὰν κινῆται, οἷον καὶ ἡ φρίκη;
Why does water appear less white if it is moved, as for instance a ripple?
διὸ καὶ Ὅμηρος ἀρχομένου φησὶ τοῦ πνεύματος
μελάνει δέ τε πόντος ὑπ’ αὐτοῦ
. ἢ διὰ δύο αἰτίας, ἐγγύθεν μὲν τῆς ὄψεως οὔσης, διὰ τὸ διιέναι τὴν ὄψιν μᾶλλον ἠρεμοῦντος, κινουμένου δὲ μὴ εὐθυπορεῖν· τὸ δὲ διαφανὲς λευκὸν φαίνεται.
Wherefore also Homer says of the wind when it begins to blow, "and the sea turns black under it." Or is it due to two causes: when the sight is near, because the sight passes through more when it is at rest, but when it is moved, the sight does not travel in a straight line; and the transparent appears white.
δι’ οὗ γὰρ μὴ διέρχεται ἡ ὄψις, μέλαν φησὶν εἶναι.
For that through which the sight does not pass, he says is black.
διὸ καὶ ὁ ἀὴρ πόρρωθεν μέλας φαίνεται, ὁ δὲ ἐγγὺς λευκός, καὶ θαλάττης τὸ μὲν ἐγγὺς λευκόν, τὸ δὲ πόρρωθεν κυανοῦν καὶ μέλαν.
Wherefore also the air appears black from afar, but white near at hand, and of the sea the part near is white, but that from afar is dark blue and black.
πόρρωθεν δέ, κινουμένης πως τῆς ὄψεως, καὶ τῷ διανακλᾶσθαι ἀθρόον τὴν ὄψιν, ἐὰν ἠρεμῇ πρὸς τὸ φῶς, κινουμένου δὲ μὴ δύνασθαι.
And from afar, because the sight is somehow moved, and because the sight is reflected in a mass if it is at rest towards the light, but when it is moved it cannot.
§23.24Διὰ τί ἐν τοῖς βαθέσι πελάγεσι τὸ κῦμα οὐκ ἐπιγελᾷ, ἀλλ’ ἐν τοῖς μικροῖς;
Why does the wave not break into foam in deep seas, but does in small ones?
πότερον ὅτι τὸ μικρὸν φερόμενον ὕδωρ διαιρεῖται ὑπὸ τοῦ ἀέρος μᾶλλον ἢ τὸ πολύ;
Is it because a small amount of carried water is divided by the air more than a large amount?
διὸ θραύεται πατάξαν μᾶλλον.
Therefore it breaks more on striking.
ἐν μὲν οὖν τῷ βαθεῖ πολὺ τὸ κινούμενον, ἐν δὲ τῷ βραχεῖ ὀλίγον.
Now in the deep sea that which is moved is much, but in the shallow it is little.
§23.25Διὰ τί οἱ πρὸς νότον τόποι ἁλυκώτερα τὰ ὕδατα ἔχουσιν;
Why do places towards the south have saltier waters?
ἢ διὰ τὸ τὴν θάλατταν ὑπὸ νότου ὠθεῖσθαι ὑπὸ τὴν γῆν κεράννυται;
Is it because the sea is mixed by being pushed under the earth by the south wind?
§23.26Διὰ τί τῶν ὑδάτων τὸ ἁλμυρὸν ἐπὶ τῷ γλυκεῖ οἴνῳ μᾶλλον ἐπιπολάζει ἢ ἐπὶ τῷ αὐστηρῷ;
Why does salty water, among waters, float more on sweet wine than on harsh wine?
πότερον ὅτι μᾶλλον ἔχει γῆν ὁ γλυκύς, ὥσπερ ἡ ἀσταφίς;
Is it because sweet wine contains more earth, like the raisin?
ἢ ὅτι βαρύτερος καὶ γλισχρότερος ὁ γλυκύς, ὥσθ’ ἧττον μίγνυται, μὴ μιγνύμενος δὲ ἐφίσταται.
Or because sweet wine is heavier and more viscous, so that it mixes less, and not mixing, the salty water stands upon it?
§23.27Διὰ τί ὅλως ἐφίσταται γεῶδες ὄν;
Why does it stand upon at all, being earthy?
ἡ γὰρ οἰκεία φορὰ κάτω.
For its proper movement is downward.
πότερον ὅτι μᾶλλον ἔχει γῆν ὁ γλυκύς;
Is it because sweet wine contains more earth?
ἢ διὰ τὴν θερμότητα, καθάπερ οἱ ἅλες;
Or because of heat, just as salt?
ὅμοιον γὰρ ἐξανθήματι.
For it is similar to an efflorescence.
ἢ δι’ ἄλλην αἰτίαν;
Or is it due to some other cause?
εἰ γὰρ οὐ διὰ τοῦτο καὶ ἐπὶ τῷ γλυκεῖ μᾶλλον, οὐκ ἄλογον· θερμότατος γάρ.
For if it is not because of this, and yet happens more on sweet wine, it is not unreasonable; for sweet wine is very hot.
§23.28Διὰ τί τὰ κύματα πρότερον φοιτᾷ ἐνίοτε τῶν ἀνέμων;
Why do waves sometimes arrive before the winds?
ἢ διότι καὶ τελευτᾷ ὕστερον;
Or is it because they also end later?
τὸ γὰρ πρῶτον πνεῦμα ὡσανεὶ προδιαλύεται τοῦ ὠσθέντος κύματος· ἀφικνεῖται δὲ οὐκ αὐτὸ τὸ πρῶτον ὠσθέν, ἀλλ’ ἀεὶ ἡ ὧσις γίνεται τοῦ ἐχομένου.
For the first wind is, as it were, dissolved before the pushed wave; and it is not the first pushed wave itself that arrives, but the pushing of the adjacent wave always takes place.