62 REV. PROF. G. F. WEIGHT, ON THE INFLUENCE OF THE 
Egypt, whose life depends upon innumerable streams — large 
and small — which bring down their life-giving supplies of 
water in due season from the heights where it has been 
detained in unfailing cold-storage reservoirs far more regular 
and reliable than the lakes of Central Africa, which are subject 
to the vicissitudes of the annual precipitation and to the 
temporary obstruction of their outlets by the accumulation of 
vegetable matter. 
The natural influence of the vicissitudes of the Glacial Epoch 
upon the development of life in Central Asia can be readily 
perceived. The conditions leading to the increase of glaciers 
in the mountains, especially those connected with the rapid 
melting of the ice during the declining portion of the epoch, 
would greatly extend the area of fertility and promote the 
interests of all forms of life. It is interesting to learn that this 
very region, which is the traditional centre for the dispersion of 
the human race, and in which, beyond all reasonable doubt, the 
Aryan races had their original home, has recently been found 
to be an important centre of pre-historic man. Professor 
Raphael Pumpelly announces, as one of the results of the 
Carnegie Expedition to explore the pre-historic mounds of 
Turkestan, the discovery of remains of man which he estimates 
to date from 8250 b.c., and of other evidence, showing that at 
about this time man had already succeeded in accomplishing 
the wonderful feat of domesticating the ox and several other 
animals.* 
The decline of the Glacial Epoch in Central Asia is connected, 
either as cause or effect, with the subsequent diminution of the 
size of the mountain streams and the general desiccation of 
that region, thus reducing its fertility. The result of this has 
been to intensify the struggle for existence, to compel increased 
migration, and thereby to give a new impulse to new centres of 
civilization. It is worthy of mention, also, that the same 
diminution of glacial conditions in Central Asia which limited 
its capacity to support population opened up the fairest 
portions of Europe and North America and invited their 
occupation by man. In America we are but just entering upon 
our inheritance, America’s great prosperity being largely due to 
the rapidity with which we are now seizing the reserved stores 
of richness accumulated in our soil by the glacial deposits and 
by the chemical changes which have taken place during the 
thousands of years through which it has since been lying fallow. 
* See Iris Report to the Carnegie Institution , Washington , 1906. 
