502 The Geological Museum of the School of Mines, | August, 
land were ploughed up, and as the ice moved forward over the 
irregular surface, it became more or less filled with boulders, 
gravel and sand, at least to the height of the peaks and ridges 
which it crossed. Differences in the slope of the surface of ice 
above, like those which made an angle in the terminal moraine, 
due apparently to inequalities in the amount of snowfall and of 
melting upon adjacent regions, must also produce downward and 
upward currents by which these materials would be distributed 
- throughout the lower part of the ice, probably to the height of 
several hundred feet, even while crossing a nearly level area. 
By the melting of the ice-sheet at and near its terminal front, 
this detritus was exposed, through every summer, to the washing 
of many rills and small streams; but before its retreat under a 
change of climate, this melting was extended over a very wide 
area. The surface of the ice was then hollowed into basins of 
drainage and channelled by rivers, which became heavily freighted 
with the gravel, sand and clay that had been held in its mass. A 
large portion of this gravel and sand was heaped at the edge of 
the ice-sheet, where these glacial rivers descended to the lower 
open area beyond. When the ice behind them disappeared these 
deposits were left in the massive hills and ridges of stratified 
drift which form so prominent a part of these series of terminal 
moraines. [To be Continued. ] 
:0: 
THE GEOLOGICAL MUSEUM OF THE SCHOOL OF 
MINES, COLUMBIA COLLEGE. 
BY ISRAEL C, RUSSELL. 
S it is impossible for every one to visit distant lands, or even 
at all seasons to go forth into the fields and among the 
mountains in quest of geological knowledge, we desire to call the 
attention of our readers to a collection in our country which in 
a great measure will supply these wants. We refer to the Geo- 
logical Museum under the direction of Prof. J. S. Newberry, at 
the School of Mines, Columbia College, New York city. Here 
the visitor will find a most interesting display of the remains of 
the ancient inhabitants of the globe, gathered not only from the 
rocks of our own country, but also from the most distant me + 
and each arranged in its proper place in the long series. me 
“the geological museum occupies the entire third story of the 
