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ASCENT OF THE DWINA — KRASNOBORSK. 
The road which leads from Ust-Vaga to Ustiug, runs for some miles at a short 
distance from the Dwina, and the great thickness of the drift sands which here 
encumber the surface prevented our seeing the fundamental rocks. Reddish cliffs, 
however, showed themselves as soon as we regained the river banks. At Zastrova, 
six versts north of Zaletzkaya, the beds consist of a dullish red and yellowish sand- 
stone, in parts brick red, with traces of fucoid-like casts. Ihese sandstones aie 
subordinate to argillaceous red marls which have been, here and there, much bioken 
up. The vegetation now begins to assume a more southern aspect. Hops are 
seen in cottage gardens, and the larch thrives well on the undulating sandy grounds 
by which you pass from Archangel into the vast government of Vologda. 
Near Larionofskaya, a very poor hamlet, the banks of the Dwina exhibit red marls 
divided by a course of whitish marlstone 1 , and the same features are continued in 
cliffs of some altitude. On reaching the river banks further to the south, we 
found them to be composed of marls having a conchoidal fracture. We regretted, 
for a time, that we had not further examined the cliffs near Larionofskaya ; but we 
afterwards ascertained, that similar beds extend over nearly the whole province, and 
that we had already passed far beyond their line of junction with the inferior fos- 
siliferous limestone. Again, for some distance to the south of Soiga, where the 
red marls appear, the country is more than usually covered up, the sands having 
given way to a covering of tenacious, light-coloured, drift-clay. In traversing this 
clayey tract, we speculated on the possibility that a district, in which arable land 
and rich meadows had taken the place of the northern forests, might contain some 
strata of a different nature ; but when we again came upon a denuded portion, the 
same red and spotted marl peeped out again from beneath the fine alluvial mould 
of the surface, occasionally strewed over with northern boulders. The only new 
features were thin bands of a calcareous grit, in parts almost a conglomerate, with 
fragments of flinty slate, &c., which pass into an impure limestone or cornstone. 
The country near the town of Krasnoborsk is much intersected by ravines 
which run from east to west, and in crossing them we examined several sections of 
the red marls, subdivided at intervals by courses of brownish red calcareous grit 
and conglomerate. If mineral character were to be taken as a proof of their age, 
we might say that these rocks much resemble some of the bands in the Lower 
New Red Sandstone of England, particularly in containing yellow magnesian 
i To make a perfect section, we should recommend future geologists to embark at Ustiug, and descend 
the Dwina to its embouchure. 
