THE OKIGIN AND ANTIQUITY OF MAN 57 



gouging out valleys as they went and carried along 

 with them masses of stone and rock fragments which 

 w'ovo finally deposited along tlic melting front oi- l;i1<'i;il 

 areas to the glacier.^'^ Glacial sti-eams flowed fi'om under 

 tlie slowly moving ice and carried fine detritus and sand 

 many miles beyond the ice line, eventually depositing 

 this material in deltas or flood plains and burying deej) 

 aU. small objects lying upon the surface. 

 ^ The problem of the geographical center from which 

 man migrated to finally populate the earth is still un- 

 solved. Tradition has designated Central Asia as the 

 ])hice of dispersion. In Central Asia are found the re- 

 mains of sand-buried cities so ancient that the very tra- 

 ditions concerning them have perished. ^^ Moreover, the 

 wild progenitors of our domestic animals — horses, cat- 

 tle, sheep, goats, swine, dogs, camel^buffalo and fowl — 

 liad tlieir habitations in Central Asia/ 



JBut there are other considerations. Geologists tell 

 us that the land formation of the present continent of 

 I'iUrope underwent many changes in the later Tertiary 

 and during the early (()uaternary. Coincident with tlie 

 ghu'ial epochs there seem to have been alternating sub- 

 sidences and upheavals of sections of the continent. 

 There appears, however, to have been a strip of dry land 

 fairly constant in its outline which extended from the 

 valk'y of the Thames and the Rhine in northwestern 

 Europe to the present island of Java at the southeast 

 of Asia.^*^ It is in this strip of territory that the most 

 important discoveries of prehistoric man have been 

 made. 



If See figure 1(). i"*!.!!!!, up. tit.. ]i. :]77. 



li* See Keaiu". o/>. cH.. ]). 54; 15riiitoii. 1). <t. — I'ncc.s antl I'cdplcN, IS'.'O, 

 jil). Sl)-89; Ciddiiigs, F. U.— Tlic I'rinviplcs of Sociology, IDOi), pp. 21-1-210. 



