REVIEW AXl) KECOMMEXDATIONS. 
13 
While we have been surprised at the abundance of the data in natural and 
ailificial records offered by the region toward these solutions, we are impressed with 
a realization of the intimate relation in which this region stands to the Quatemar)' 
and prehistoric history' of the whole continent. Physicalh- it forms part of the 
great interior region extending from the Mediterranean to Manchuria, whose history- 
has been one of progressive desiccation, but in Russian Turkestan the effects of this 
have been mitigated by the snows of the lofty ranges and the lower altitude of the 
plains. 
Archeologically this region has, through a long period, been a center of pro- 
duction and commerce, connecting the eastern, western, and southern nations, and 
its accumulating wealth has made it repeatedly the prey of invading aniiies. It 
has been from remote time the field of contact and contest between the Turanian 
Fig. 8. — A Mosque o( Mediaeval Samarkand. 
and Aryan stocks ; but its problems, both physical and archeological, are parts of the 
greater problem underlying the study of the development of man and his civilization 
on the great continent and of the environment conditioning that development. 
The many fragmentar}- peoples sur\i\ing in the remote comers and in the pro- 
tected mountain fastnesses of Asia, preserving different languages, arts, and customs, 
indicate a very remote period of differentiation, with subsequent long periods for 
separate development. The)- point also to the long periods of unrest and battling 
in which the survivors of the vanquished were forced into their present refuges. 
And this unrest was probabh- the remote protot>-pe of that which in the later pre- 
historic and historic time sent out its wa\-es from the Aralo-Caspian basin. It was 
probably from the beginning a condition in which the slowh- progressive change 
toward aridity in interior Asia was ever forcing emigration outward, displacing 
