[Sidenote:  Arid lands as areas of arrested development.]

Deserts and steppes lay an arresting hand on progress.  Their tribes do not develop; neither do they grow old.  They are the eternal children of the world.  Genuine nomadic peoples show no alteration in their manners, customs or mode of life from millennium to millennium.  The interior of the Arabian desert reveals the same social and economic status,[1165] whether we take the descriptions of Moses or Mohammed or Burckhardt or more recent travelers.  The Bedouins of the Nubian steppes adhere strictly to all their ancient customs, and reproduce to-day the pastoral nomadism of Abraham and Jacob.[1166] Genealogies were not more important to the biblical house of David and stem of Jesse than they are for the modern Kirghis tribesman, who as a little child learns to recite the list of his ancestors back to the seventh generation.  The account which Herodotus gives of the nomads of the Russian steppes agrees in minute details with that of Strabo written five centuries later,[1167] with that of William de Rubruquis in 1253, and with modern descriptions of Kalmuck and Kirghis life.  The Gauchos or Indian pastoral halfbreeds of the Argentine plains were found by Wappaeus in 1870 to accord accurately with Avara’s description of them at the end of the eighteenth century.[1168] The restless tenants of the grasslands come and go, but their type never materially changes.  Their culture is stationary amid persistent movement.  Only when here or there in some small and favored spot they are forced to make the transition to agriculture, or when they learn by long and close association with sedentary nations the lesson of drudgery and progress, do the laws of social and economic development begin to operate in them.  As a rule, they must first escape partly or wholly the environment of their pasture lands, either by emigration or by the intrusion into their midst of alien tillers of the soil.

But while the migrant shepherd originates nothing, he plays an historical role as a transmitter of civilization.  Asiatic nomads have sparsely disseminated the culture of China, Persia, Egypt and Yemen over large areas of the world.  The Semite shepherds of the Red Sea deserts, through their merchants and conquerors, long gave to the dark Sudan the only light of civilization which it received, Mohammed, a Bedouin of the Ishmaelite tribe, caravan leader on the desert highways between Mecca and Syria, borrowed from Jerusalem the simple tenets of a monotheistic religion, and spread them through his militant followers over a large part of Africa and Asia.

[Sidenote:  Mental and moral qualities of nomads.]