314 The American Geologist. ^^^'' "o- 
time, but to orig-inally unequal and patchy deposition, anal- 
ogous with the tendency of the ice-sheet in its Wisconsin 
stage to add till to the hights of growing drumlins, in local- 
ities of their abundant development, while sometimes leaving 
little till o>r none on intervening low tracts of the bedrock. 
With these explanations I think we may accept a moderate 
estimate of the age of the Kansan drift, consistent with a 
duration of the entire Glacial period as only about 100,000 
years, and with a close relationship of the lowan and Wiscon- 
sin stages, both belonging to the Champlain epoch or time of 
land depression terminating the Ice age. 
Man lived in the region of the Somme valley, France, be- 
fore the great elevation of northern lands which caused them 
to be mantled with snow and ice. From the Old W'orld, the 
original home of our species, mankind migrated to America 
at some undetermined, time before or during the Ice age. If 
the migration was contemporaneous with the glaciation of the 
northern half of our continent, the passage, whether from 
northeastern Asia or northwestern Europe, or from both, took 
place along the shores of the sea, where the vast ice-sheet was 
bordered by a strip of coastal land like that now fringing the 
Greenland ice-sheet, but which has since been deeply sub- 
merged. 
That America was peopled very long ago is ascertained 
geologically by traces of man contemporaneous with the clos- 
ing scenes of the Ice age in Delaware, New Jersey, New York, 
Ohio, Indiana, Kansas, Iowa, Minnesota, and Manitoba. The 
latest and most noteworthy proof of this was the discovery 
last year of a human skeleton under loess of the lowan stage 
of glaciation near Lansing, Kansas, as described by the pres- 
ent writer in this magazine last September. At least it is to be 
said that this is the view very confidently held by Winchell, 
myself, and others who have later visited and examined that 
locality. 
But a different view is held by Chamberlin, Holmes, and 
others, who, from their examination of the Lansing section, 
think the deposit above the skeleton to be more probably refer- 
able to Postglacial time. With much care and effort they have 
also worked and written, during the last ten years, against all 
the geologic evidences, which others have thought acceptable, 
