It is joined by four main tributaries, the Drina, Bosna, Vrbas and Una.
The Una rises on the Croatian border, and, after skirting the Pljesevica Planina, in Croatia, turns sharply to the north-east; serving as a frontier stream for 37 m.
Finally, in 1791, the treaty of Sistova again fixed the line of the Save and Una as the Bosnian frontier.
Thus " Socratitus " is merely an accident of the substance "humanitas," or, as it is put by the author of the treatise De generibus et speciebus, 1 " Man is a species, a thing essentially one (res una essentialiter), which receives certain forms which make it Socrates.
The army, commanded in chief by Una under the VIth Dynasty for raids in Sinai or Palestine, comprised levies from every part of Egypt and from Nubia, each under its own leader.