CENTEAL AJSB EASTERiT NEVADA. 377 



The following notes concerning the Manhattan mill and some of the 

 details of its working methods will probably suffice to give an idea of the con- 

 dition of the milling business about Austin. 



The Manhattan mill has 20 stamps, 10 roasting furnaces, and 14 pans, 

 capable of crushing, roasting, and amalgamating 20 tons of ore per day, or 

 600 tons per month, if fully employed. The process by which the ores are 

 treated resembles in its general features that by which the first-class ores of 

 the Comstock lode are reduced, which has been already described m a pre- 

 ceding chapter. The amalgamation, however, is performed at the Manhat- 

 tan mill in pans, instead of barrels. The principal operations of the process are 

 dry-crushing, roasting with salt in reverberatory furnaces, and amalgamation in 

 pans. The ore is prepared for the stamps by a "Thunderbolt," or Gardner 

 crusher. This is set up near the entrance to the mill, and reduces the larger 

 pieces to fragments about the size of an egg. This crusher is less widely used 

 than the Blake, though the manager of this mill expresses satisfaction with its 

 operation. After being broken by the crusher the rock is thrown directly 

 upon a drying floor which is about 8 feet wide by 16 feet long. This is con- 

 structed generally like that already described at Ball's mill, in Washoe Val- 

 ley, except that the heat in this instance is provided by causing the flue, which 

 leads from the roasting furnaces to the stack, to pass under the drying floor 

 on its way. When thoroughly dried the rock is fed to the stamps. These are 

 arranged in four batteries of five heads, weighing about 700 pounds, drop- 

 ping 8 inches, 85 limes per minute. The screens are of brass wire-cloth, with 

 40 meshes to the linear inch. The capacity of these stamps is about one ton 

 per head in twenty-four hours. The batteries are inclosed in tight, wooden 

 dust-chambers that are about 8 feet high, and having ample space for men to 

 enter and shovel out the pulverized ore. A tramway is laid through the cham- 

 bers so that a car may be filled in them and moved thence, on the track, to 

 the roasting furnaces, discharging directly into the hopper through which the 

 furnace is supplied. 



The furnaces are ten in number; four of them, of more recent construc- 

 tion than the other six, are similar in most respects to those already described 

 at Washoe. The older furnaces differ in their manner of discharge, having an 

 aperture in the hearth, near the stirring door, which may be opened when 

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