140 MmmG INDUSTEY. 



and ore-house, smith and carpenter-shops. The latter are not shown in 

 their full dimensions. The ground adjacent to the establishment, not in- 

 cluded within the limits of the drawing, is conveniently arranged for 

 wood and timber yards, weighing houses near the ore-house, and all other 

 desirable appurtenances for the prosecution of the business. Plate XVI 

 gives a sectional view of parts of the same establishment, showing the man- 

 ner in which the pumping engine transmits power, by means of the pump- 

 wheel, pitman, and bob, to the pump rod in the shaft ; also the arrangement 

 of one of the hoisting engines with its winding reel, rope, sheave, and cage. 

 The pumping engine of the Savage mine is one of the Corliss pattern ; a 

 beam engine with vertical cylinder, 26 inches in diameter and 6 feet in 

 stroke, a very beautiful and efficient but costly machine. On the crank- 

 shaft is a pinion, 3 feet in diameter, which drives the main wheel, 10 feet in 

 diameter, carrying the pitman by which the balance-bob and the connected 

 pump-rod are set in motion. The wheel and pinion have a 16-inch face. 

 The former is constructed with mortise gearing, consisting of a cast-iron 

 wheel, the periphery or face of which, instead of having iron teeth, as usual, 

 consists of a stout rim provided with spaces into which wooden teeth are 

 carefully fitted. The engine is usually run at 10 or 12 strokes per minute, 

 though calculated to make 27 per minute. The pump-rod makes a stroke of 

 7 feet, under ordinary circumstances, about four times per minute, though 

 capable of much higher duty, if required. 



The bob is of wrought and cast iron combined. The pump-rod is made 

 of pine, in sections 30 feet long and 12 inches square, joined together as 

 already described. The weight of the rod, with its iron straps, is partly bal- 

 anced by the counter-weight on the bob at the surface, besides which there 

 are three balance bobs at stations below ground. The pumps have been 

 already described. The plungers are 10 and 12 inches in diameter. The 

 column of elevation is 14 inches. 



There are three hoisting engines, one for each compartment of the shaft. 

 They are 16-inch horizontal cylinders, having 36 inches length of stroke, and 

 are fitted with slide valves and link motion. 



Three boilers furnish steam to all these engines. They are set in the 

 adjoining boiler-room, partly shown in the drawing. They are each 16 feet 



