MOUNTAINS AND THEIR ORIGIN. 113 
it, outweighed the Alleghanies, the Rocky Moun- 
tains, the Coast-Chain, and the Andes. 
When we compare the present state of our 
knowledge of geological phenomena with that 
which prevailed fifty years ago, it seems difficult 
to believe that so great and important a change 
can have been brought about in so short a time. 
It was on German soil and by German students 
that the foundation was laid for the modern sci- 
ence of systematic geology. 
In the latter part of the eighteenth century, 
extensive mining operations in Saxony gave rise 
to an elaborate investigation of the soil for prac- 
tical purposes. It was found that the rocks con- 
sisted of a succession of materials following each 
other in regular sequence, some of which were 
utterly worthless for industrial purposes, while 
others were exceedingly valuable. The Muschel - 
Kalk formation, so called from its innumerable 
remains of shells, and a number of strata under- 
lying it, must be penetrated before the miners 
reached the rich veins of Kupferschiefer (copper 
slate), and below this came what was termed the 
Todtliegende (dead weight), so called because it 
contained no serviceable materials for the useful 
arts, and had to be removed before the valuable 
beds of coal lying beneath it, and making the 
base of the series, could be reached. But while 
n 
