814 Scientifie Intelligence. 
present knowledge of the figure of the earth, geologists should 
not be prevented from speculating on the probability of great, 
changes in the obliquity of the ecliptic having caused former great 
variations of temperature.” Mr. belt also touches on the lower- 
ing of the sea-level by the accumulation of ice over the land, and 
says that, on the supposition that the ice was equal in the two hemis- 
pheres at the same time (the view he sustains), the lowering of the 
sea-level “could not have been less than 2000 feet, and may have 
been much more.” 
Since any lowering of the water line of the ocean by the abstrac- 
tion of water to make the Glacial ice would have been alike on a 
the coasts of the world, Mr. Belt’s estimate of the amount in the 
Glacial period is open every where to demonstration. On the 
Atlantic border of North America, such a change—which is equiv- 
alent to a rise of the land of 2000 feet—would have led to an im- 
mense amount of valley-excavation along the many rivers; and 
_ valleys, so recently made, should still intersect the alluvial, 
t 
channels. There d 
any part to the fiords of Glacial latitudes; and, more than this, 
present sea-level. The same fact is true of other continents 
of the globe. Moreover, the deep submergence of Behring’s 
Strait (now but 180 feet in depth), and of the region around, by 
* Manual of Geology, 2d edit., p. 541. 
