vial lowlands or
coastal plains of the Torrid and Temperate Zones. The restless, mobile,
unbound shepherds of the arid lands have never long been contained by
the country which bred them. They have constantly encroached upon the
territory of their better placed neighbors, invading, conquering,
appropriating their fields and cities, disturbing but at the same time
acquiring their culture, lording it over the passive agriculturists, and
at the same time putting iron into their weaker blood. It is the
geographical contact between arid steppes and moist river valley,
between land of poverty and land of plenty, that has made the history of
the two inseparable.[1055]

[Illustration: CULTURAL REGIONS OF AFRICA AND ARABIA.]

[Sidenote: Mobility of pastoral nomads.]

Every aspect of human life in the steppes bears the stamp of mobility.
The nomad tolerates no clog upon his movements. His dwelling is the tent
of skin or felt as among Kalmucks and Kirghis, or the tent wagon of the
modern Boer[1056] and the ancient Scythian as described by Herodotus.[1057]
"This device has been contrived by them as the country is fit for it,"
he says,--level, grassy, treeless. The temporary settlement of shepherd
tribes is the group of tents, or the ancient _carrago_ camp of the
nomadic Visigoths,[1058] or the _laager_ of the pastoral Boers, both a
circular barricade or corral of wagons.

[Sidenote: Tendency to trek.]

Constant movement reduces the impedimenta to a minimum. The Orochones, a
Tunguse nomadic tribe of eastern Siberia, have no furniture in their
tents, and keep their meager supply of clothing and utensils neatly
packed on sledges, as if to start at a moment's notice.[1059] The only
desirable form of capital is that which transports itself, namely,
flocks and herds. Beyond that, wealth is limited to strictly portable
forms, preferably silver, gold and jewels. It was in terms of these,
besides their herds, that the riches of Abraham and Lot were rated in
the Bible. That the Israelites when traveling through the wilderness
should have had the gold to make the golden calf accords strictly with
the verisimilitude of pastoral life.[1060] Moreover, that these enslaved
descendants of the Sheik Abraham, with their traditions of pastoral
life, should have simply trekked-ruptured the frail ties of recently
acquired habit which bound them to the Nile soil, is also in keeping
with their inborn nomadic spirit. Similar instances occur among mode