Germany. In the sandy, infertile Baltic plain the land is held in severalty, inheritance taking place in the direct line. The oldest son, sometimes the youngest, remains on the patrimony, while all the other children go forth into the world to make their way alone. Primogeniture prevails, in short. In the fertile parts of Würtemberg, on the other hand, where the village community long persisted, all the children share alike on the death of the father. Each one is a constituent element in the agrarian social body, for which reason no emigration of the younger generation takes place. The underlying reason for this difference may have been that in the north the soil was already saturated with population, so to speak. The farms were too poor to support more than a single family, a condition absent in the south. The net result of such varying customs after a few generations would be to induce a constant Teutonic emigration. Military expeditions may have been merely its superficial manifestation. It would, of course, be unwarranted to suggest that any one of these factors alone could cause the great historic expansion. Nevertheless, it is far from improbable that they were contributory in some degree.
When all the Teutonic tribes broke over bounds and went campaigning and colonizing in Gaul and the Roman Empire, a second great racial wave swept over Germany from the east. Perhaps the Huns and other Asiatic savages may have started it; at all events, the Slavic hordes all over the northeast began to move. Here we have another case of a widespread social phenomenon, military on the surface, but involving too many people to be limited to such forcible occupation. There is abundant evidence that these Slavs did not always drive out the earlier population. They often merely filled up the waste lands, more or less peaceably, thus infiltrating through the whole country without necessarily involving bloodshed.
There are several ways in which we may trace the extent of this Slavic invasion before we seek to apply our criteria of physical characteristics. Historically, we know that the Slavs were finally checked by Karl the Great, in the ninth century, at the so-called Limes Sorabicus. This fortified frontier is shown on our map on page 66, bounding the area ruled in large squares diagonally. The Slavic settlements may also be traced by means of place names. Those ending in itz are very common in Saxony; zig also, as in Leipzig; a in Jena; dam in Potsdam—all these cities were named by Slavs. Indications of this kind abound, showing that the immigrant hordes penetrated almost to the Rhine.
It seems impossible that the movements of a people should be traced merely by the study of the way in which they laid out their vil-
