372 On the Physical Geography of the Alps. 
only be well followed out, in proportion as the general upcast of 
the strata approaches the perpendicular. For the strata often 
eserve over large tracts the same strike and dip, and are fre- 
quently cut through by a series of valleys without suffering any 
change. One might expect that in the great basin-like depres- 
sions the inclination of the strata would be in some degree altered. 
till we must consider that the uprise or tilting of the strata is 
unusualiy steep in the Alps; a partial withdrawal, therefore, may 
happen without any very striking disturbance of the inclination 
and the succession of strata, and is far more possible than under 
the conditions of horizontal stratification. Occasionally only are 
we led to notice very striking disturbance of the stratification, 
particularly in the limestone Alps, and there indeed, where the 
greatest irregularity of the valley-bottoms has been effected by 
tricts, and are altogether wanting in the central parts, where crys- 
talline slates abound and where the elevation is most regular. 
Chapter x. (pp. 222-234) contains M. Adolph Schlagintweit’s 
observations on the Geological formation of the Oetz Valley a 
the Tauern Range. In speaking of the Alps generally, the au- 
ite, are widely distributed, mad with great regularity, ‘aamaatioat 
the Alps, stretching from the Maritime Alps, in important moun- 
tain-“ groups,” to Mont Blanc, and continuing on to the eastern 
extremity of the Alps, where they suddenly disappear beneath 
the tertiary formations. The constituent rocks are very various. 
Gneiss and mica-schist ——- with manifold modifications ; ; 
geological formations with orographical conditions, and enu- 
meration of treatises on the structure of the Alps in general, an 
of the Oetz Valley in particular, our author proceeds to be in 
detail the geological constitution of the Oetz-thal “group ;” pre- 
mising, that the great regularity of elevation over so considerable 
an area, and the pretty equal distribution of the formations, are 
here very remarkable. In this extensive district no true granite 
is found. Gneiss, hornblende rock, and mica-slate are the most 
prevalent rocks; amongst these the last preponderates in extent, 
and indeed of itself composes the highest parts. Besides these, 
at the boundaries of the mountain-“ group” there are some nal- 
row ridges of grauwacke-like rocks of red sandstone and clay- 
slates; and at the northern limit towards the valley of the Inn 
there are tracts of limestone. The latter reach to inconsiderable 
heights Ne and evidently belong to the great limestone ranges 
in the north, separared by the Inn valley. These, together with 
