﻿516 P^'of. Milne — Across Europe and Asia. 



than an hour we had crossed the flying bridge, and were safely at the 

 end of this section of my journey : the distance from Tomsk being 

 about 1559 versts, or 1036 English miles. Irkutsk is a large town, 

 of about 30,000 inhabitants, containing many fairly handsome build- 

 ings. It is situated on the N.E. side of the Angara, opposite to its 

 junction with the Kiver Irkut. Like St. Petersburg, it may be said 

 to have been built upon a marsh. In 1652 there were only two 

 houses upon the present site, but soon after, in 1686, by order of the 

 Government, the town as it now appears began to rise. Although 

 the town itself is flat, the surrounding country is undulating. All 

 along the sides of the rivers, and running for some distance up the 

 slopes of the hills, there are beds of alluvium. On the hills them- 

 selves there is a covering of yellowish earth from two to three feet 

 in thickness, which, from the fragmentary stones it contains, can be 

 seen to have been derived from the disintegration of the subjacent 

 rocks. These are in the main a grey and yellowish sandstone, 

 slightly micaceous, and somewhat gritty. This is quarried and used 

 as a building stone in the few places where stone is required about 

 the town. In some places it is conglomeratic. Whilst examining this 

 rock upon the north-east side of the town, I found several thin vein- 

 like seams of coal. These veins, which had a brownish lignitic 

 character, were from two to four inches in thickness. In the sur- 

 rounding districts many outcrops of this material have been found, 

 which unfortunately appears to lack more in quality than it does in 

 quantity. From fossils which have been found in this formation, its 

 age, as I have before stated, when speaking of the coal-fields of the 

 Urals, is probably Jurassic. About 40 miles to the north-west this 

 overlies a limestone, which is probably of Devonian age, but even 

 about this there is some doubt. Besides the strata on these two 

 horizons, the only other rocks in the district appear to be either 

 highly metamorphic or else volcanic in their origin. The former of 

 these rocks are well developed along the valley of the Eiver Tunka. 

 The rugged mountains which bound this valley, called the Tunkusian 

 Alps, can be seen from Irkutsk. Mr. Tchersky, who has explained 

 this district, has described a remarkable series of graduations as 

 occurring there. The series commences with limestone, passes 

 through pyroxenic rocks, and ends with rocks that are granitic. 



Up this same valley perched boulders of a local origin have been 

 found. Their discoverer, Mr. Tchersky, attributes their origin to 

 glacial action, but on this point local geologists are not agreed. The 

 only other phenomena which can be assigned to the action of ice are 

 the scratched stones in the alluvium of the river-banks, but these 

 are only such as are produced every year. So, as I have before said, 

 we have not yet any undoubted evidence of polar ice-caps or large 

 glaciers. 



Besides coal, which I have spoken of. Iron ore. Gypsum, and 

 Kaolin are found in the neighbourhood. A small quantity of gold 

 is also worked, and once there was a lead-mine. The best returns 

 appear to be derived from the salt springs, as at Tailma, which was 

 a station I p issed through before reaching Irkutsk. 



