GOLD MINING IK COLORADO. 



527 



which is a smooth, round shaft. The upper ends of the sides, a, a, are con- 

 nected by two short pieces of chain with the cable, by which the whole is sus- 

 pended. The upper cross-piece, h, is a spreader of wood, protected on the 

 outside by a bar or plate of iron. The frame moves in the shaft between 

 guide-rods, c, c, which are embraced by flanges, d, d, on the sides of the 

 frame. The body of the skip, when in an upright position, is supported by 

 the lower cross-piece, Z>, to which it is attached by means of boxes, e, e, and on 

 which it may turn freely when it arrives at the dump. A wheel, W, made 

 with a broad face and deep flange, is attached to each side of the skip, and, 

 moving in the space between the guide-rod, C, and the shaft-timber, F, they 

 hold the skip in an upright position in the shaft, but on reaching the dump 

 the wheels enter the groove G, allowing the top of the skip to fall forward 

 while the bottom is raised in the frame, assuming the position shown in the 

 left-hand figure. K the frame be raised still further the skip goes on in an 

 inverted position, the wheels bearing upon the surface indicated by the line 

 i i, but on being lowered again below the level of the dump, the skip resumes 

 its upright position without any aid, and continues on its way down the shaft. 



Water is raised, by the same skip, from the sump at the bottom of the 

 shaft, as no pump has yet been provided. In order to discharge the rock and 

 water at different dumps, a switch, H, is provided, which may be fixed in the 

 position shown in the left-hand figure, or moved, by means of a rod, h, into the 

 position indicated by dotted lines. In the former case the wheels of the skip 

 enter the groove G, at the lower dump ; while in the latter case they pass 

 upward to the groove G', at the upper dump. 



The surface works of the mine consist of hoisting machinery, command- 

 ing both shafts, and a crushing mill containing 22 stamps. These appur- 

 tenances are so placed that the power required for their operation is furnished 

 by one engine. Both shafts are covered by spacious shaft-houses, connected 

 by an intermediate building, in which are the smith and carpenter shops, office, 

 and room for selected or smelting ore. 



The drawing on Plate XXXII presents a plan of the hoisting works, 

 showing the arrangement of the winding machinery. The stamp mill, not 

 shown in the drawing, is west of the hoisting works and driven by the same 

 power. 



