542 
DRIFT AND ERRATICS OF NORWAY. 
cerns us to point out, is the manner in which the coarser block detritus has been 
piled up, and to endeavour to explain the manner in which we conceive it has been 
swept from the north. 
Completely agreeing with Prof. Forchhammer, that the northern detritus in 
Denmark must have been accumulated under w r ater, we can nevertheless scarcely 
venture to adopt the whole of his belief, that it can all have been aggregated by 
ordinary submarine currents, brought into play by moderate and gradual oscillations 
of the land. A much more powerful cause than any now in action is, we think, 
required to explain the surface phenomenon of Scandinavia. 
Whether we examine the hard and crystalline rocks on the sides of the Nor- 
wegian fiords, or traverse the promontories towards the interior of that country, 
some of which, in the southern region, are upwards of 2000 feet, and others in 
the north about twice that height above the sea, we find the surface powerfully 
eroded, frequently much worn down and polished, and their surface marked in 
numerous places by parallel furrows and innumerable fine mechanical striae. 
Either at the head of the Gulf of Christiania, or in the high grounds of Ringe- 
rigge, all the striae and markings which fell under our observation are directed 
from north-north-west to south-south-east, and this is the normal direction assigned 
to the greater number of the Norwegian scratches by Professor Keilhau. That 
author has observed such striae upon the surface of opposite and high plateaux, 
where the detrital materials which produced such striation must have passed 
athwart valleys of great depth, and whose base is now occupied by lakes. In such 
cases he imagines that the amount of detritus must have been so mighty, as to fill 
up all the intervening cavities, though in other valleys the direction of the striae is 
found to deviate from the normal line, and to sweep, as by an eddy, round the 
flanks of the mountain. In Norway, at least in the southern parts, with which we 
are alone acquainted, the northern faces of the promontories are much worn down, 
abraded, polished and scratched, whilst their southern faces, generally more abrupt, 
are in a rough and natural condition 1 . Such, in fact, are many of the rocky isles, 
or “ skars 2 3 ,” which the traveller sails by, as he. ascends by Gottenburg to the bay 
1 Professor Keilhau pointed out to us a phenomenon in the upland valley above Christiania, more than 
two miles from the sea, and certainly 200 or 300 feet above it, which is of high interest in showing that 
all the scratches of the rock must have been brought about by submarine agency . The Silurian rocks on 
the sides of the valley are there perforated by Pholades apparently of existing species. 
3 “ Skar,” Swedish for a sea-rock. “ Os,” Swedish for a pile of gravel, is “ osar” in the plural. 
