GOLD MINING IN KLONDIKE. 235 



the limited area intersected by the auriferous creeks which radiate from 

 the Dome. 



Some of the gold adheres to quartz, which exactly resembles that 

 of the veins in the adjoining schists; and it is fairly certain that 

 the metal came from quartz veins in the Klondike schists. 



On the other hand it is certainly most remarkable that so little 

 auriferous quartz has been found; at the time of my visit hundreds 

 of quartz claims had been staked, but very few had been shown to 

 contain any gold whatever; neither do the quartz boulders of the White 

 Channel appear to be auriferous, or even mineralized. And yet it can 

 hardly be doubted that where the valley gravels are rich in gold above 

 their intersection with the White Channel the metal must have been 

 derived from quartz veins in the schists. 



In one instance I found direct evidence bearing on this question. 

 In Victoria Gulch, a streamlet which descends into El Dorado Creek 

 on its left bank high up the valley, have been found small flat 

 crystals of gold of peculiar shape known as 'spinel twins.' In visiting 

 a quartz vein at the head of Victoria Gulch (near the summit of the 

 divide between El Dorado and Bonanza creeks), which had been lately 

 opened and found to contain visible gold, I noticed precisely similar 

 crystals. Here, at any rate, there can be little doubt that the gold in 

 the creek has been derived from quartz veins in the schist. 



No crushing has yet been carried on in Klondike ; the gold has been 

 entirely won by washing the gravels. 



The chief difficulties of Klondike mining are due to the permanently 

 frozen ground, which has led to certain peculiarities in the methods 

 adopted. Every yard of gravel which is sluiced must first be thawed, 

 either by artificial means or by exposing it to the rays of the summer 

 sun after stripping off the overlying muck ; for it is impossible to work 

 the frozen ground with pick or spade, or even with dynamite. 



Until recently shafts were sunk or tunnels were driven by labori- 

 ously thawing the ground with hot stones or wood fires; and I saw 

 both methods in operation during my visit. The latter process — fire- 

 setting, as it is called — is, in fact, quite frequent. A layer of dry 

 wood is piled up against the face of the gravel, blanketed behind by 

 a layer of green wood, ignited, and allowed to burn itself out; twelve 

 hours of burning would thaw out little more than one foot in depth; 

 and the process is then repeated. 



Upon the larger properties this method has been entirely replaced 

 by 'steam-thawing.' In this four- to six-foot lengths of iron piping, 

 tipped with steel nozzles, are inserted into the gravel, and steam is 

 forced through them at a pressure of about 120 pounds. These pipes 

 are known as 'points'; one point is inserted to about each square yard, 

 and is driven in gradually by taps from a hammer; each point will thaw 



