489 
To the eastward of the crystalline zone, stratified sedimentary rocks 
appear, such as slates, sandstones, conglomerates, indurated shales 
interstratified with trappean rocks of a dioritic or diabasic nature. 
These compose by far the greater part of the eastern side of the 
central chain, exhibiting everywhere there huge foldings. This ex- 
tensive formation of sandstones and slates in some places is over- 
laid uncomformably by a carbonaceous system. The relation of 
these sedimentary formations one to another , and their exact geo- 
logical age, as compared with the European series of formations, 
has at yet not been distinctly made out . 1 The extensive develop- 
ment of limestones, such as are peculiar to the European Alps, is 
totally lacking; and a simple glance at the above sections shows 
furthermore , that only the eastern half of a complete mountain- 
system has been preserved, while the western half is buried in the 
depth of the main. The eastern foot of the mountains is formed 
by tertiary and alluvial deposits broken through by volcanic rocks. 
The period of volcanic energy was one of upheaval; and since it 
closed we see no evidence of there having been any submergence 
of the island on the East side, whilst on the West coast, the evi- 
dence derived from the mountains rising directly from the sea and 
penetrated by the fiords, indicates rather a gradual submergence. 
Another very remarkable feature of the magnificent snow clad 
range of the Southern Alps, is the enormous amount of glacier 
surface and glacier action, and moreover, the constant traces of 
those glaciers having at no remote period extended far below their 
contorted schist, but is rarely found in situ. Quartz-reefs are confined to the 
upper schists. 
External to all the above formations we have a series of Tertiary rocks; the 
lowest of these, however, may possibly be of the Upper Mesozoic age. The series 
consists of coarse conglomerates, sandstones and shales, containing estuarine shells, 
and associated with thick deposits of brown coal of excellent quality. The shales 
with the coal contain ferns and dicotyledonous leaves. This carbonaceous formation 
is generally tilted at considerable angles and is unconformably overlain by the newer 
Tertiary rocks. These consist of two series, the one freshwater, occupying basins 
or depressions in the schistose rocks of the interior, the other marine, confined to 
the coast-line and low altitudes.” 
1 See Chapter 111. 
