The Birmingham age-herald., 1908-10-11


 over a slender copper cable. From small substation at the mouth of the mine the current is carried on insulated cables to any part of the workings. The little motors do not take up much room and are capable of great power. High speed pumps and blowers are coupled di- rect to the motor shaft, doing away with all belts and gears. The lectric light is safe and convenient; the electric hoists do their work better and quicker than any other form of power hoists, and the underground electric locomotives are rap idly replacing the mules in hauling the ore.
 We read great deal about the recent identification of steam railroads on the surface of the earth, but 1t Is only in mining circles that one hears 1t said that the network of tracks in the anthracite coal mines has spread until the under- ground mileage is almost as great as the mileage of the so-called anthracite roads. The operation of a coal mine today in- cludes the management of an electric railway system fully as intricate and diff ficult as any surface electric road.
 Mine owners were first to see the value of the electric locomotive for mine haul ing, and today thousands of electric To- comotives are taking the place of mules on the underground railways. One of the first electric mine locomotives was built { by the General Electric company in 1887, [ long before an electric locomotive for sur face work had been perfected, and only a year later the first electric street rail- way system was installed. How well this early locomotive was built is evidenced by the story told of an attempt to get 1t i to exhibit at the Pan-American exposi- tion. One of the officials wrote and asked If the old locomotive could be resurrected from the scrap heap for the occasion. The manager of the mine wrote back very indignant letter and said it could not be resurrected, as 1t had never been in the scrap heap and was still in opera tion, and that they could get the loco- motive only by sending one to take its place and do it's work during it's absence. As the excavations get deeper and deeper and the gangways extend farther and farther from the shafts, electric hosts and electric locomotives are the most economical agents for handling the ores.
 There are four distinct kinds of power used in mines, exclusive of rope haulage for steep slopes-mules, compressed air, steam, and electricity. In the volume of work done mules remain far in the | lead. Steam is going backward. Com pressed air is about stationary Elec- tricity is the coming factor. Every year the gangways are extended farther from the shafts. As the hauls increase, the problems of underground transportation become more serious. Some 17,0O0 mules are still employed in and around the an- thracite coal mines, but in many cases mere distance has already disqualified mule power. Compressed air locomotives, though used in considerable number, have proven less economical than electric loco motives. There are few steam engines in the mines, as combustion of any kind is not desirable in coal mines, on account of the risk from gas explosions. Within three years. from 1903 to 1906, the num- Der of electric locomotives in the anthra- cite mines of Pennsylvania not including those on top of the shafts, grew from S4 to 2O5
 The electric mining locomotive has been the direct means of keeping the price of coal within the reach of the consumer. If, as the mine grew deeper and more difficult, the old methods were still em- ployed, the cost of getting the coal out would be so great that the price would have to be raised several dollars a ton. Electric haulage provided means for get ting the coal out of the mines at very low cost, because it does the work so much quicker and better than mule pow er In some of the older mines 1t is three miles ITOH tue DIodSt, where lne coal is mined, through the gangways to the shaft. In these days of electric mining the ore or coal is drilled, prior to blasting, with compressed air or electric drills, and the air compressors are nearly al- ways driven by electric motors. The men work under electrict light. The ore Is loaded in small cars and hauled to the hoist with an electric locomotive pulling A whole train of loaded cars. The cars are raised to the surface with electric hoists and hurried away on another elec- trc road to the stamp mills, the breakers or the smelters.
 In nearly every mine water causes the most trouble, and the problem to keep the underground workings dry is very serious one. Mines that cannot be drain- ed by tunneling have to be pumped dry. The new automatic centrifugal pump, driven by an electric motor, works auto ,matically to keep the mines free from
 water. whenever the water rises to a
 certain level 1t starts the motor and the pump removes the surplus until 1t drops
 below the point where the power Is shut 1 off automatically.
 1 Most of the large mines in this country
 are now thoroughly lighted with fncan-
 descent lamps.
 In Mexico and other Central and South