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GUIDEBOOK OF THE WESTERN UNITED STATES. 



By climbing steadily from Garfield the railroad is here about 200 

 feet above the bottom of the canyon, and the traveler may look 

 down on the left and note all the activities of a mining town. (See 

 PI. XCV, A.) The canyon is very narrow, and the town consists of 

 a single street with scarcely room enough for houses on both sides. 

 The view from the train would be fine were it not that the road is 

 chiefly carved through the mountains. From time to time the train 

 emerges from the portal of a tunnel and crosses one of the side can- 

 yons on a steel trestle 200 feet or more high. The traveler may then 

 have a good view of the canyon, but the mines are mostly above the 

 town, so that they are not visible uAtil the train stops. 



When the traveler alights from the train he finds himself high up 

 on the side of the canyon and at its largest fork. He may well stop 

 here to look at the surroundings, for it is doubtful if he will find as 

 good a viewpoint without considerable climbing. He may look in 

 vain for the mines, but instead he will see the wall of the canyon 

 before him creased with horizontal benches and on each of these 

 benches an enormous steam shovel lifting the ore and its overburden 



some of the metals, such as lead, zinc, 

 and arsenic. The fumes are therefore 

 turned down into long semicircular 

 flues, where the dust particles collect, 

 or they are cooled and condensed to 

 solids in chambers. In some plants 

 the particles are collected by being 

 passed through pipes fitted with a cen- 

 tral insulated wire, the pipe and wire 

 forming the two poles of a high-tension 

 electric field. The dust becomes 

 charged with electrostatic energy and 

 is driven to one pole of the field, where 

 it accumulates and is periodically col- 

 lected. Arsenic is also saved by pass- 

 ing the fumes through thousands of 

 woolen bags treated with zinc oxide or 

 lime. At present many plants use the 

 fumes in the manufacture of sulphuric 

 acid, which is again utilized in the 

 leaching of copper ores. These devices 

 have brought a great change in smelt- 

 ing. Many years ago a dense volume 

 of smoke marked the position of the 

 smelter stack, but now the smoke nui- 

 sance is largely abated. 



Copper smelting to a certain extent 

 is similar to lead smelting, but the 

 products must be treated somewhat 

 differently. Roasters, reverberatories, 

 and blast furnaces are used, but the 



operation of the blast furnace, instead 

 of making copper bullion, results in 

 copper matte, a product that contains 

 copper, sulphur, and iron. This matte 

 is again treated in converters which 

 have an opening in the top to dispose 

 of the fumes and to receive the matte 

 when the converter is charged. An 

 intense blast of air is forced in from 

 the sides, allowing oxygen to combine 

 with the sulphur and form sulphurous 

 gases which are led away from the 

 top, and after about 2 hours the matte 

 is " blown " into the product known as 

 blister copper, which contains about 

 98 per cent of pure copper. If much 

 gold and silver is present the blister 

 copper is further refined. 



A large copper smelter in operation 

 is a most impressive sight. It con- 

 sists of a row of blast furnaces belch- 

 ing forth white-hot slag. Strings of 

 cars take the fiery material to the slag 

 dump, and glowing streams of the 

 melted matte flow from the furnaces 

 into large kettles. Traveling cranes 

 pick up the kettles and pour the molten 

 matte into the converters, where, with 

 an intense light, the work of " blow- 

 ing " begins, which changes the matte 

 to blister copper. 



