In East Prussia it is easily seen that the geographical names are not German. Neither are they Russian. The Old Prussian, a member of the Lithuanic family of languages, was spoken here as late as the sixteenth century, remains of which, in the shape of a catechism, are extant. This is the language of the ancient _Æstyi_, or _Men of the East_, which Tacitus says was akin to the British, an error arising from the similarity of name, since a Slavonian (if such were the original source of his information) would call the two languages by names so like as _Prytskaia_ and _Brytskaia_, and a German (if the authority were Germanic) by names so like as _Pryttisc_ and _Bryttisc_. The Guttones, too, of Pliny, whose locality is fixed from the fact of their having been collectors of the amber of East Prussia and Courland, were of the same stock. The name by which they were known to the Slavonians within the historical period was _Guddon_=_Gothones_, _Guttones_. In West Prussia the extermination or amalgamation of the native Lithuanians was earlier. We have no specimens of their language. We know, however, that the country took its name from them. They seem to have been the most western members of their family. The southern frontier of the present Prussia is Polish. Prussian Poland--the Duchy of Posen--is now, as it always has been, Sarmatian, Slavonic, Lekh, Lygian. Pomerania, too, retains vestiges of its Slavonic population in the _Kaszeb_, _Kassubes_, or _Kassubitæ_, occupants of the peninsula and islands at the mouth of the Oder. The name, too, of the province at large, is Slavonic; _po_=_on_+_more_=_sea_=_coast_-_land_. The Isle of Rugen was one of the last strongholds of Slavonic Paganism, as is shown by its numerous antiquities, and by the evidence of history. The famous temple of the _Obotrite_ Slavonians was there; though Mecklenburg rather than Pomerania was the part of the continent to which they belonged. In Prussian Silesia, the _Serskie_ of Lower and the _Srbie_ of Upper Lusatia, still Slavonic, retain their language, and represented the older population of the whole country. The Saale was the original boundary between the Germans and the Slaves, all between Thuringia and Poland belonging to that stock. Certain as this is from the accounts of the conquest under the Carlovingian empire, the details are difficult for Prussian Saxony, Altmark, and Brandenburg. The _Hevelli_ were on the Hevel: the _Stoderani_, _Brizani_, _Bethenici_, _Dossani_, and _Smeldingi_ filled up much of the valleys of the Oder and the Elbe: we cannot, however, fill up the whole tract. Yet, the names of the _Marches_, or _Borders_, show that the encroachment was gradual. First, and nearest to Germany, is the _old_ march (_Altmark_); after this, the Middle march (Mittel mark); and then the March of the Ukrians (Uckermark), all originally frontiers between the encroaching Germans and the retiring Slavonians, and all frontiers within the historical period.