LARGE TRACTS OF PERMIA FORMED ANCIENT LANDS. 
521 
their comparative abundance on the higher undulating grounds between it and 
Krasnoborsk, whilst the lower country in which the Dwina flows towards Arch- 
angel is almost, if not entirely, exempt from them. That tract forms, indeed, a 
portion of the broad sand-covered tracts between Cargopol and the Dwina which 
have been already described, as being free from every sort of northern drift. 
These facts, including what we have said of the position of the blocks to the 
south of Jurievetz, where they lie on the highest portions of a tract composed of 
finely laminated, loamy sands, appear to us to favour strongly the view on which 
we shall afterwards dwell, that the great erratics (so far detached from the sources 
of their origin and often separated therefrom by wide regions in which no trace of 
such detritus is found) were probably floated to their present habitats in former ice- 
bergs, when the sands in question formed the bottom of a sea, which extended from 
the shores of Scandinavia, and in which the icebergs sailed southwards with the 
current, until arrested by the higher grounds in question. But what was the con- 
dition at that time of these higher grounds ? By inspecting the Map the reader 
will perceive, that the country around Ust-Sisolsk, and thence to the edge of the 
Timan range, — in short, the upper grounds in which the feeders of the Vitchegda 
spring, form the extreme limit in that direction of every Scandinavian erratic. Still 
further to the north-east, the Timan range constitutes their eastern girdle, for no 
trace of them has we believe been detected beyond it, in the basin of the Petchora. 
The ancient elevation of that range explains this feature of the phenomenon. 
In our last chapter on the Ural Mountains, it has been shown, that a large 
portion of Siberia and the whole of the Ural chain must have been above the 
waters during long periods antecedent to our sera ; and we would now observe, 
that such elevations as those, which affected the central ridge of these mountains, 
could scarcely have taken place without occasioning a corresponding rise over a 
considerable area on the west. May we not, therefore, suppose, that the same 
elevations which last raised the Ural Mountains and Siberia, and rendered those 
tracts the residence of mammoths and other wild animals, had also raised the large 
area of the governments of Penn, Viatka and Orenburg, which lies between the 
eastern limit of the Scandinavian blocks and the edge of the Ural Mountains ? 
of aerolites w ! i i c b fell from heaven. Our mmeralogical curiosity was loused, and, unseen, we contrived to 
chip off a small fragment from the block, which from its blackened and polished external aspect (due to 
long adoration and the smoke of incense) might really have passed for an aerolite when it proved to be 
a true granitic northern boulder. So much for the legend and St, Procopius. 
