THE DRIFT HAS ACQUIRED NEW MATERIALS IN PASSING TO THE SOUTH. 519 
end is higher, with small indented bays into which heaps of rounded boulders have 
been lodged under the side of the cliffs. The explanation of this peculiarity of 
outline will be entered upon in the sequel, in treating of the much better exam- 
ples of similarly-shaped and eroded isles and promontories in Scandinavia. We 
will now only observe by the way, that in the large wood trade which is carried on 
between Onega and England, the rafts of timber now find their resting-place from 
the tidal influence, in the southern bay of the little Ki-ostrof, just as the boulders of 
old did ; that side being now as well protected from the roll of the northern surge, 
as it was of old, from the violent current of the northern drift. 
We have thus endeavoured to explain the nature of the northern drift, as well 
as the manner in which it has been deposited, along the northern frontier of the 
sedimentary deposits of Russia, and the reader will, we hope, have perceived, that 
in general such detritus is most accumulated on plateaux and high grounds, and 
particularly on their southern slopes. We have also shown, that it occurs in north 
and south zones of greater and lesser width and length. It has further been stated, 
that in a broad space of country between Yitegra and Archangel, of small elevation 
and at no great distance from the source of their origin, erratic blocks are very 
rarely to be detected, whilst in approaching their sources, or the crystalline 
nucleus of the White Sea, they increase. 
Let us now follow these trainees to the interior. To the south of the govern- 
ment of St. Petersburg, the Valdai Hills, like other high grounds to which we have 
adverted, have arrested vast quantities of blocks (granite, gneiss, greenstone and 
porphyry of Finland), which in many parallels of longitude are profusely spread 
over the southern talus of these hills, and have been transported to Moscow, and 
to great distances south of that city. Taking the direction of the great mass of 
drift which has passed to the south and south-south-east, we may, indeed, confi- 
dently refer to the same origin the blocks which are traceable at intervals as far 
southwards as Voroneje (see Map), a distance of about 700 or 800 miles from the 
nearest edge of their parent country. Following the drift in the longitudinal 
parallel of the lake of Onega, which we have indicated as a powerful zone, we 
found the regions around Tcherepovetz, Mologa, Yaroslavl and Vladimir, even as 
far southwards as Jelatma, or Yelatma, not only encumbered with large erratic 
blocks, but with such vast masses of gravel, clay and sand, that it is quite impos- 
sible to detect a trace of the subjacent rocks over very wide tracts, even in the 
beds of the Volga and the deepest cutting rivers. The body or matrix of the drift 
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