50 THOMAS COMMERFORD MARTIN 



It is, therefore, not to be understood that electric loco- 

 motives find their onty employment in coal mines. An in- 

 teresting illustration of the extensive application of the elec- 

 tric mine locomotive is to be found also in the Quincy copper 

 mine, at Hancock, Mich. The Quincy company has installed 

 15 electric locomotives, one of which is on the 4,400 foot level, 

 current being supplied from the surface through substation 

 transformer plants located underground. Another instance 

 which might be quoted is the 8 ton mine locomotive at the 

 Highland Boy Gold Mining company's mine, at Murray, Utah, 

 employed for hauling slag cars, and using double overhead 

 trolle}^ so as to dispense entirely with the track as a return 

 circuit. 



Thus far the subject of mine traction has been considered 

 from the point of locomotives supplied by overhead or under- 

 running trolleys, or by third rail, with current from a distant 

 source of supply. It is possible, however, to employ seK- 

 propelling or automobile locomotives, equipped with storage 

 batteries, so as to dispense entirely with the dangers and in- 

 convenience of tracks and wires charged with exposed live 

 current. The weight of the battery and the space that it 

 necessarily occupies, however, increase the size and weight 

 of the locomotives, and thus place a restriction upon this 

 method of traction in many mining operations. Their use 

 is therefore more particularly to be noted in connection with 

 exterior work, and locomotives used for such work have con- 

 siderable haulage capacity. 



A further modification of traction or haulage methods 

 is found in the movable automatic loader used by the Illinois 

 Steel company. It is difficult to classify this apparatus, 

 but it serves to move ore, and therefore belongs possibly 

 as much in the transportation as in the loading group. The 

 machme consists of an endless chain of metal arms or scoops 

 mounted on a stout metal table or base, which in turn is 

 mounted pivotally on a truck, to enable it to adjust itself 

 to the pitch of the ground and to the height to which the 

 material is to be elevated in loading — as, for example, to 

 a line of the trolley mine cars. The chain of scoops, which 

 is driven by an electric motor, passes around sprockets ar- 



