THe TCE AGE 
North Pole, remained in the grip of the ice sheet for over 
two thousand years longer than France. 
Baron Gerard de Geer of Sweden has made the most 
promising attempt at measuring the time that has elapsed 
since the height of the last great glacial stage. In his 
article in Antiquity of September, 1928, he says: 
In 1891 I had noticed, in several places [in America] laminated clays, 
similar to the late glacial melting sediments in Sweden; these I had 
found, by long continued investigations, to represent the annual de- 
posit from the melting water on the border of the retreating ice edge. 
I had succeeded in identifying such varves from one point to 
another, and ultimately worked out a systematic plan for the elabora- 
tion of a continuous time scale. 
These varves, or annual bands, as Baron de Geer satis- 
fied himself, corresponded to the yearly fluctuation of the 
glaciers, due to the oncoming heat of summer (Plate 22). 
If carefully measured over some section of country which 
represents the whole retreat of the ice since the end of 
the last glaciation, they will indicate pretty closely the 
number of years that have elapsed since that retreat 
began. They will also tell us, by their inequalities, which 
were the warmer and which the cooler periods of years. 
If we find that such warmer and cooler periods occurred 
at the same time in different parts of the earth, we shall 
know that the major cause of all these successive glacia- 
tions must have been of cosmic character. Such a dis- 
covery would also probably throw much new light on 
the variability of the sun’s radiation, to which these world- 
wide, contemporaneous glacial changes would in all 
probability be due. 
Aided by a band of enthusiastic university students, 
Baron de Geer actually carried through the laborious 
undertaking of counting and measuring the varves in 
Sweden. He found that in that country approximately 
8,700 years have elapsed since the latest glacial stage 
finally closed. His pupil, Doctor Antevs, made extensive 
counts and measurements in the United States and 
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