6o 



ALASKA GEOLOGY 



At the time of my visit active mining work was chiefly 

 confined to the no-foot level, much stoping being done 

 there, and all ore taken from the open pit above being run 

 down to that level in chutes and hoisted from there 

 through the main shaft. 



The 220-foot level was also well opened out by drifts 



FIG. 14. DIAGRAMMATIC SECTION OF TREADWELL MINE; OPEN PIT. 

 Scale, i inch = 150 feet. 



and cross-cuts, and stoping had already been begun on a 

 limited scale. Below this, levels cross-cutting the deposit 

 had been run out at 330 and at 440 feet, and were open to 

 inspection, but no drifting had yet been done from them. 

 About 2,000 tons of ore a day were being lifted from this 

 mine through the two shafts. 



Two sections across the deposit were roughly measured, 



- 



s 



4) 



I 



Sf 



FIG. 15. DIAGRAMMATIC SECTION OF TREADWELL MINE; 44O-FOOT LEVEL. 

 Scale, i inch = 150 feet. 



one at the open pit level, the other in the cross-cut on the 

 44o-foot level (reproduced in figs. 14, 15). From these 

 sections it may be seen that the width of the deposit be- 



