No. 2.] SPENCER — COPPER-MINING. 75 



cared for, can safely be expected to last 18 months. In one 

 shaft that I know, the ropes had been used as long as possible, 

 and broke twice each of them after a use of 29 months. At 

 Portage Lake, from the Quincy Rock-House to the Stamp Mill, 

 there is a descent of nearly 500 feet in a distance of halt a mile, 

 the steepest grade having an inclination of 14° ; two full cars 

 having a weight of 8 tons are run down an inclined tramway by 

 gravity, and bring up two empty cars of half that weight, these 

 trains of cars being connected by wire ropes over a drum at 

 the summit of the hill. The rope, which is one inch in diameter, 

 has been subject to constant use for 12 years, and although 

 it has broken once (from accident) it is not yet worn out. The 

 ropes which are not galvanized are always kept well tarred to 

 prevent them from rusting. The transportation between the 

 shaft, rock-houses, and stamp mills is also by various other contri- 

 vances than the oue just mentioned. Sometimes when the railroads 

 are not too long and nearly horizontal, the cars are attached to 

 stationary engines by endless ropes, or again they are sometimes 

 drawn by locomotives, by horses, or, where the distance is short, 

 manpower is used. The car attached to endless ropes is so 

 arranged that it dumps its contents, — this being accom_ 

 plished by means of two small wheels near the back part of the 

 box of the car, which project, so that when it passes a station near 

 its destination, it runs up an inclined plane lifting the back end 

 and causing the frout to open. 



The transportation of men in the mines is a subject of 

 interest. Ladders are usually placed in each shaft. A stair, 

 way is used in the incline shaft of the Phoenix Mine, while in 

 another shaft of low inclination at the Central Mine, the miuers 

 are transported by a car capable of carrying 25 men. At this 

 mine, some years ago, 13 men were aiding up in a skip, when the 

 rope broke, and the accident resulted in the death of 10 meu, the 

 other three escaping, as the skip was thrown from the track and 

 jammed, instead of going all the way to the bottom of the 

 shaft. The officers are very strict in order to prevent the men from 

 risking their lives by riding in the skips. In some of the deeper 

 mines, as the Quincy, Pewabic, Cliff, Calumet and Hecla, man- 

 engines have been constructed at very great cost. The longest of 

 these is in the Quincy Mine,* built down an incline shaft of 54° to 

 56° dip, to a depth of about 1-450 feet. This contrivance con- 



* See isometric view of man-engine. 



