﻿562 Pt'of. Milne — Across Eurojw and Asia. 



This would suggest that the constancy in the general character of 

 the gold obtained from the Lena, as compared with that from the 

 Amoor, is either due to their having originated from diiferent sources, 

 or, what is perhaps as probable, that those great causes which acted 

 in laying out the beds of alluvium in which they occur, also acted 

 in separating the various qualities of gold according to their respec- 

 tive specific gravities, that which was light being carried farthest 

 from its source as compared with that which was heavier. If there 

 is any probability of such an action ever having taken place, then 

 we might suppose that the gold of the Lena district has travelled 

 farther from its origin than that in the Amoor. 



In the consideration of such an action, the average relative sizes of 

 the transported particles is an important factor. In the gold of 

 Eastern Siberia such metals as platinum or iridium, which are so 

 common in the Urals, are but seldom found. A little is, however, 

 obtained from the washings at Nertchinsk. 



Whilst in Irkutsk I paid several visits to the smelting works, 

 where all the gold of Eastern Siberia is cast into ingots. There is 

 a similar establishment at Barnaul for Western Siberia. At these 

 works I had every opportunity kindly given me of examining 

 large quantities of gold from various localities. The bulk of what 

 I saw was more or less roughly granular, many of the grains being 

 as large as peas. I saw many indications of the formation of 

 crystals, from which I concluded that such gold had not travelled 

 very far from the position in which it had been originally deposited. 



The gold mining all over Eussia is under Government control, 

 which always specifies that, after obtaining a grant of land, 

 one must commence to work upon it within a given time. The 

 places which are generally worked are the banks and beds of small 

 tributary rivers, but more especially the beds. Near the mouth of 

 the river the yield is generally less than it is higher up. In such 

 places the alluvium may be sixty feet in thickness, whilst the bed 

 containing the gold, which may be below all this, is only perhaps 

 seven feet in thickness. Tbe workings generally commence at the 

 mouth of a stream, and work up the valley down which it flows to- 

 wards its source. The first operation is to sink a number of trial 

 shafts at right angles to the direction of the valley. These go 

 down to the bed rock. From the gold-sand which generally lies 

 upon this rock samples of 10 pouds each (3601bs.) are taken, then 

 washed, and afterwards the yield for 100 pouds is calculated. After 

 this has been done at several points, and the results are satisfactory, 

 a dam is thrown across the river, and the water is sent round one 

 side, along the edge of the valley, instead of down the course in 

 which it originally ran. If near the dam they have to sink, say, for 

 example, thirty feet, in order to reach gold, then they must also 

 sink thirty feet below the bed at some point below these workings, 

 and from it cut a drain in order to carry off any water which may 

 accumulate at the point where they are extracting the gold. 



This is only one system which is adopted in mining and pro- 

 specting. There are others specially for prospecting, which are 



