NOTES. 61 
cepted, even with considerable limitation the geperal conclusions he 
had presented concerning the glacial period, might have foretold, 
said Prof. Agassiz, that the southern hemisphere would present 
the counterpart of all these phenomena. And yet he supposed that 
many of his friends thought he was over-sanguine when, in a letter 
to the Superintendent of the Coast Survey, he had told what he 
expected to find, in this matter, during the Hassler Expedition. 
The hesitation which was prevalent concerning these generaliza- 
tions arose from the view which many entertained of the true cause 
of the phenomena. Many thought that the greater extension of gla- 
ciers in the Alps and most parts of Europe was to be ascribed to 
the former existence of large sheets of water in the north of Africa, : 
from the evaporation of which great amounts of snowy deposition 
could be formed upon the Alps, and thus enlarge the glaciers. 
But he would ask those who entertained this view how a sheet of 
water in Africa could have made great sheets of ice upon the 
continent of North America? There had been a disposition more 
or less outspoken among geologists to view the phenomena of the 
greater extension of glaciers in a former period as the result of 
local glaciers. He believed he was the only one among investiga- 
tors of that subject who had urged a distinction between local gla- 
cial phenomena and the general glaciation of our continents. It 
was because he was familiar with the distinction between these two 
sets of facts that he had always held, from the very beginning of 
his investigations, that there was a time when our earth presented 
climatic conditions so totally different from those now obtaining, 
that the northern hemisphere was covered by an extensive sheet 
of ice, and that the phenomena to be ascribed to the agency of 
that sea of ice moving from north southward were those uniform 
glacial appearances which we find over continental expanses, ee: 
traces of which we find even in high elevations. He ha 
convinced that whoever should explore the southern netted 
on an extensive scale would find the evidence from extensive gla- 
ciation on the southern hemisphere as well as on the northern, but — 
that the trend of the southern ice sheet and the transportation of — 
bowlders would be reversed. Instead of moving from the north 
southward as in the northern hemisphere, the movement should be — 
from the south northward, and the accumulations of loose-mate- _ 
rials in southern moraines should present an arch curving north- 
ward. He could say that he had seen in the southern hemi- 
