138 Remarks on the Level of the Molasse in the Eastern Alps. 
reaches even near 3000 feet, if we compare the brown coal 
bed on the Pass of Obdach and the deepest Artesian borings 
at Vienna, where they have not yet sunk through the miocene 
formation, although they reach the present level of the sea ?* 
If the level of the formation indicates, as at first supposed, 
the level of the ¢ertiary sea itself, it follows that, at the close 
of the tertiary period, the different tracts of the country 
must have been upheaved in a very different measure. But 
whilst there is nowhere in the whole country a single ap- 
pearance of such unequal local upheavings, the intimate and 
regular connexion between the height of the level and its 
situation, more or less inland and remote from the open sea, 
points to a totally different cause, upon the nature of which 
Mr Simony’s very accurate and complete soundings of the 
Lake of Hallstadt, near Salzburg, appear to have thrown some 
light. This irregularly-shaped lake, surrounded by precipi- 
tous cliffs, naturally also shews beneath water-mark (water- 
level) steep, rocky banks, which, however, are suddenly cut 
off at a certain depth by a tolerably even surface, evidently 
the plane of deposition of the nearly horizontal recent strata. 
Where the lake is narrowed this plane rises nearer and 
nearer to the surface of the water, so as almost to reach it, 
and yet without standing in any relation to deltas, which of 
course are here set aside, and are not considered as being 
foreign to the subject. 
Now, considering the known tertiary deposits, it appears 
highly probable that their level does not indicate the former 
level of the sea, but only marks the plane of deposition, which 
being more or less deep, owing to the sea being more or less 
open, so that the more you advance along the fiords into the 
interior of the eastern Alps, and the more of course, the bottom 
of the ancient sea was shallowing, the more you see the level 
of the tertiary deposits arising, until they attain an extreme 
height of 3000 feet, which will have been but little below the 
water-mark. 
To avoid all misunderstanding, let it be remarked, that 
there has been no question here of diluvial terraces, which 
* Vienna lies 545 English feet above the sea, 
