INTRODUCTION TO SOCIOLOGY 97
fact, establishes also among them a relative conformity of structure and life.
In Asia and Europe the direction of the mountain chains is chiefly from east to west ; this natural phenomenon is important. It is in relation to the direction of the rivers and valleys, and it explains the migrations, slow or rapid, peaceful or violent, of Asia and Europe.
In Africa, America, and Australia, the general orographical division is from north to south, save the Atlas, which is attached to the European system, as, indeed, the country itself is allied to Europe by the nature of its climate, vegetation, population, and history.
As for the division in use between Europe and Asia, it is arbitrary. From the Pacific to the Atlantic, by the Atlas, the Thian-Chan, the Kuen-Lun, the Himalayas, the Caucasus, the Taurus, the Alps, the Carpathians, and Pyrenees, the chain is continuous, the system is unique. Europe is dominated oro- graphically by the Asiatic system, of which it is the continua- tion; the imperialism of Russia and Turkey still links it to Asia and its system of absolute monarchies, to the tradition of which even republican France is subjected. Furthermore, in Europe as in Asia, the ramifications of the principal peninsulas which project from the central trunk, such as Kamtchatka, Corea, the two peninsulas of India, Arabia, Italy, and Scandinavia, run from north to south. Only the Ural, from the Ural sea to the gulf of Kars, constitute a natural barrier to the direction of rami- fications, indicated above between Asia and Europe. 1
This general orographical structure, with its special, though regular, ramifications, has exercised considerable influence, not only on the direction of civilization as a whole, but also on its particular forms and tendencies. In the valleys, large or small, bounded by mountains, groups are nomadic and isolated, living during the centuries in isolation from one another, and produ- cing varied social structures. The homogeneous and successive waves of immigrations are divided into small groups; varieties,
'ELISEE RECLUS, Glographie universelle; HOUZEAU, Histoire du sol de /' Europe; A. MAURY, La terre et Vhomme.
