SECTION FROM UST-KOIVA TO VERKHOTURIE. 
389 
dips to the west, under the millstone grit, in the manner previously described, and 
represented in the woodcut, p. 126. 
Here then the geologist has reached the western term of the more violent disturb- 
ances due to the outburst of the plutonic rocks and the upheaval of the Uralian 
axis, and from this point to the west the carboniferous limestone simply folds over 
in broad undulations capped by millstone grit, occasionally containing a little coal ; 
whilst all these more ancient palasozoic rocks subside beneath conglomerates and 
deposits ot the lower country. Such conglomerates arranged in horizontal strata 
we met with at the mouth of the river Usva and opposite the village of Komasino, 
where they alternate with beds of sandstone. They are entirely made up of frag- 
ments of the adjacent palaeozoic rocks on the east, and certain fragments of carbo- 
niferous limestone, from the size of a child’s head to that of the fist, mingled with 
pebbles of quartz, sandstone, chert, Lydian stone, &c. Such beds, similar to those 
observed in the same position on the route between Kongur and Ekaterinburg 
(p.354), tell an unambiguous tale, and assure us that one of the great elevations 
of the Ural chain took place after the formation of the carboniferous limestone and 
millstone grit, the fragments of which have been deposited at the foot of the highly- 
inclined and broken formations which have been described. 
Transverse Section of the Ural from Ust-Koiva on the west by Bissersk and the 
Katchhanar to Turinsk and Verkhoturie on the east (PL II. fig. 5). — Having en- 
deavoured to explain the nature of the deposits on the western flank of the North 
Ural, as exposed in the gorges of the rivers Serebrianka and Tchussovaya, we now 
beg our readers to repass with us into Siberia, on a more northern parallel, — one 
by which we could not have travelled without the united assistance of our lamented 
friend Prince Butera and the Imperial Government. A part of this journey only, 
viz. to the gold mines of Chresto-vodsvisgensk, can be accomplished in the tilegas 
and light carts of the country, the central ridge being with difficulty passable on 
horseback. 
To the east of Ust-Koiva, a plateau of millstone grit is succeeded by carboniferous 
limestone, similar to that on the Tchussovaya, on which is situated the Zavod of 
Alexandrofsk. Undulating and unaltered strata, chiefly carboniferous, continue 
a little to the east of that place, when the older grits and grauwacke (Devonian ?) 
with subordinate limestone are found penetrated by intrusive rocks. 
These intrusive rocks stretch out in a zone from north to south in the meridian 
of Bissersk, the chief Zavod of the tract, and are most apparent about twelve 
3 E 
