The nature of their country, and the rivers by which it is intersected, greatly favour this mode of resisting attacks. For the land is level, well watered, and abounding in pasture; while the rivers which traverse it are almost equal in number to the canals of Egypt. Of these I shall only mention the most famous and such as are navigable to some distance from the sea. They are, the Ister, which has five mouths; the Tyras, the Hypanis, the Borysthenes, the Panticapes, the Hypacyris, the Gerrhus, and the Tanais. The courses of these streams I shall now proceed to describe.
The Ister is of all the rivers with which we are acquainted the mightiest. It never varies in height, but continues at the same level summer and winter. Counting from the west it is the first of the Scythian rivers, and the reason of its being the greatest is that it receives the water of several tributaries. Now the tributaries which swell its flood are the following: first, on the side of Scythia, these five- the stream called by the Scythians Porata, and by the Greeks Pyretus, the Tiarantus, the Ararus, the Naparis, and the Ordessus. The first mentioned is a great stream, and is the easternmost of the tributaries. The Tiarantus is of less volume, and more to the west. The Ararus, Naparis, and Ordessus fall into the Ister between these two. All the above mentioned are genuine Scythian rivers, and go to swell the current of the Ister.
From the country of the Agathyrsi comes down another river, the Maris, which empties itself into the same; and from the heights of Haemus descend with a northern course three mighty streams, the Atlas, the Auras, and the Tibisis, and pour their waters into it. Thrace gives it three tributaries, the Athrys, the Noes, and the Artanes, which all pass through the country of the Crobyzian Thracians. Another tributary is furnished by Paeonia, namely, the Scius; this river, rising near Mount Rhodope, forces its way through the chain of Haemus, and so reaches the Ister. From Illyria comes another stream, the Angrus, which has a course from south to north, and after watering the Triballian plain, falls into the Brongus, which falls into the Ister. So the Ister is augmented by these two streams, both considerable. Besides all these, the Ister receives also the waters of the Carpis and the Alpis, two rivers running in a northerly direction from the country above the Umbrians. For the Ister flows through the whole extent of Europe, rising in the country of the Celts (the most westerly of all the nations of Europe, excepting the Cynetians), and thence running across the continent till it reaches Scythia, whereof it washes the flanks.
All these streams, then, and many others, add their waters to swell the flood of the Ister, which thus increased becomes the mightiest of rivers; for undoubtedly if we compare the stream of the Nile with the single stream of the Ister, we must give the preference to the Nile, of which no tributary river, nor even rivulet, augments the volume. The Ister remains at the same level both summer and winter- owing to the following reasons, as I believe. During the winter it runs at its natural height, or a very little higher, because in those countries there is scarcely any rain in winter, but constant snow. When summer comes, this snow, which is of great depth, begins to melt, and flows into the Ister, which is swelled at that season, not only by this cause but also by the rains, which are heavy and frequent at that part of the year. Thus the various streams which go to form the Ister are higher in summer than in winter, and just so much higher as the sun's power and attraction are greater; so that these two causes counteract each other, and the effect is to produce a balance, whereby the Ister remains always at the same level.
This, then, is one of the great Scythian rivers; the next to it is the Tyras, which rises from a great lake separating Scythia from the land of the Neuri, and runs with a southerly course to the sea. Greeks dwell at the mouth of the river, who are called Tyritae.
The third river is the Hypanis. This stream rises within the limits of Scythia, and has its source in another vast lake, around which wild white horses graze. The lake is called, properly enough, the Mother of the Hypanis. The Hypanis, rising here, during the distance of five days' navigation is a shallow stream, and the water sweet and pure; thence, however, to the sea, which is a distance of four days, it is exceedingly bitter. This change is caused by its receiving into it at that point a brook the waters of which are so bitter that, although it is but a tiny rivulet, it nevertheless taints the entire Hypanis, which is a large stream among those of the second order. The source of this bitter spring is on the borders of the Scythian Husbandmen, where they adjoin upon the Alazonians; and the place where it rises is called in the Scythic tongue Exampaeus, which means in our language, "The Sacred Ways." The spring itself bears the same name. The Tyras and the Hypanis approach each other in the country of the Alazonians, but afterwards separate, and leave a wide space between their streams.
