Bisbee daily review., 1908-07-05

stopes to a main hoisting shaft (the Sacramento), and the hoisting of this ore by means of Slips to a belt con veyor distributing plant on the sur fact. At the power house air is com pressed for use by power drills, and, in some places, for hoisting) and electricity both in the form of alter mating and direct current, the former being used generally for power and lighting, and the latter for operating trolleys underground.
 The power house is now completed and in operation. although only small load has been transferred to it from other plants. There are four Sterling boilers Of large capacity. us
 ing oil for fuel, three ngsrs0I-
 Rand compressOrs with a total dis placement of 9300 cubic feet of free air per minute; three Curtis steam turbine generating sets of 500 K. w. each, and rotary conveTters for chang ing alternating to direct currents. The auxiliary equipment is unusually complete. The boilers are equipped with Greene .ecouOmizers and Foster superheaters. Tn feed water is pumped by threG-thrOw Gould electric pumps, of which there are two, fer safetEu There is also supplied a steam pump, in case Of accident to the electric machinery. The con- tdensing water is pumped to a cooling flower by rotary pumps supplied by the P. H. & F. M Roots Company. lThese are also operated by direct cur trent electric motors of the variable speed type. so that their speed is automatically regulated by a float in a hot well. The cooling tower is To- cgted high enough so that cold water lfiows by gravity to the condensers. From the power house electric transmission lines are run to all shafts for lighting purposes and to lsupply the necessary power to Oper- ate pumps, saw mills, etc. The pow
 CT as distributed is very completely lmetered to detect losses and inef- l lfieient use. After the change is made
 to hoisting at the Sacramento shaft, | the Lowell, Spray and Holbrook en- Igines will be operated by compressed lair. The tCzar engine will be geared l to an electric motor, and the Gardner ! and Sacramento shafts, being com iparatively near the power house, will be operated by steam generated at that plant. The transferring of prac-
 tically all of the hoisting of ore to the ISacramentO shaft has cut down the power consumed at the present shafts
 sufficiently to make it economical to ! operate in this manner, using the isteam engines now in place for com | pressed air.
 The amOupt of water pumped 3s
 not large. and will be handled entirely lby electric pumps. These have been made by the Allentown Rolling Mills Ithere being three pumps of 300 gal Ions capacity each located at the CzaT lshaft, two of 100 gallons each at the 1 lHolbrook, two of 50 gallons at the Spray. and two of 10O gallons at the Lowell. These pumps are made in duplicate so that in case of accident la spare unit will always be ready to tput into operation. They are however,
 geared considerably lower than the IcustOmary speed for such pumps, in
 order to avoid accidents as far as possible.
 1 As most of the water pumped car
 ries considerable sulphuric acid and
 sulphate Of copper, the pump columns
 are all lined with wood, as this has lbeen found to resist acid water ef-
 feCtual!y. The present pumps lO-
 cated at the same shafts will be main tained in working order, so that in
 case of unusual floods they may bS used to keep the mine dry.
 The electric underground haulage | system will be installed on the 400. 600, 800, 1000 and 126G levels, and again on the 1400, when that is open ! ed up. It has been necessary to drive many drifts to use for this pUr- pose and they have been located in | tsOlid ground to Obviate repairs and Idelays due to bad ground. This work i has been finished. the track and wires ! laid. The motors are made by the 1 Goodman Manufacturing Company. ! The motor cars used are of the gable bottom, sids-dumping type, and may be dumped and the doors relOcked automatically Chute loaders will ' fill the cars and make them up into trains at convenient points for trans mission to the Sacramento shaft There they will be dumped into small storage bins while being drawn across them, and then. returned for other loads. From these bins at the . sSelGL LdultAiO Sl4dlI lut OIt VIII Dt loaded into three-ton skips, which Idump automatically, onto a belt con IyeyoT. manufactured by the Stepen- lsOn-Adamson company. which will carry it down the hill about 150 feet to the railroad tracks. There are located at this point four tracks ac, Icommodating 3G cars. holding 1S80 tons of ore. They will be loaded from two belts running lengthwise be tween the four tracks, and the ore will be dropped into the cars by dumping carriages which move con. Itinually back and forth, the whole length of the train being loaded. By moving continually the ore will be linked thoroughly in the cars. 4 sam pie will be taken for analysis at the
 smelter, and the ore weighd by pass ling over a Blake-Dennison continuous
 weighing machine.
 The Sacramento hoisting engine
 now erected, was made by the Nord berg Manufacturing company. and is
 Of an entirely new type in this coun ltry. It uses round rope and is a tan ldem compound condensing engine
 Although it Is operated by the same
 levers as the simple engine now in use
 it has a number of automatic devices
 for altering the power of the engine by increasing the receiver pressure
 between the cylinders for emergency