226 THE UTILIZATION OF NIAGARA. 



used-up water from the water wheels of the Niagara Falls Paper Com- 

 pany. The turbines (fig..3, PI. IX) have to generate 5,000 horsepower each, 

 at a distance of 140 feet underground, and to send it up to the surface. 

 For this purpose the water is brought down to each by the supply pen- 

 stock, made of steel tube, and 1\ feet in diameter. This water impinges 

 upon what is essentially a twin wheel, each receiving part of the stream 

 as it rashes in at the center, the arrangement being such that each 

 wheel is three stories high, part of the water in the upper tier serving 

 as a cushion to sustain the weight of the entire revolving mechanism. 

 These wheels, which have 32 buckets and 36 guides, discharge 430 

 cubic feet per second, and they make 250 revolutions per minute. At 

 75 per cent efficiency they give 5,000 horsepower. The shaft that runs 

 up from each one to the dynamo is of peculiar and interesting construc- 

 tion. It is composed of steel three-fourths inch thick, rolled into tubes 

 which are 38 inches in diameter. At intervals this tube passes through 

 journal bearings or guides that steady it, at which the shaft is narrowed 

 to 11 inches in diameter and solid, flaring out again each side of the 

 iournal bearings. The speed gates of the turbine wheels are plain cir- 

 cular rims, which throttle the discharge on the outside of the wheels, 

 and which, with the cooperation of the governors, keep the speed con- 

 stant within 2 x>er cent under ordinary conditions of running. These 

 wheels are of the Swiss design of Faesch and Picard, and have been 

 built by I. P. Morris & Co., of Philadelphia, for this work. 



The dynamos thus directly connected to the turbines are of the Tesla 

 two-phase type (fig. 4, PI. X). Each of these dynamos produces two 

 alternating currents, differing 90 degrees in phase from each other, each 

 current being of 775 amperes and 2,250 volts, the two added together 

 making, in round figures, very nearly 5,000 horsepower. This amount 

 of energy in electrical current is delivered to the circuits for use when 

 the dynamo is run by the turbine at the moderate speed of 250 revolu- 

 tions per minute, or, say, 4 revolutions per second. Here, then, we have, 

 broadly, a Tesla two-phase system embodying the novel suggestions 

 and useful ideas of many able men, among whom should be specially 

 mentioned Mr. L. B. Stillwell, the engineer of the Westinghouse Elec- 

 tric Company, upon whom the responsibility was thrown for its success. 



Each generator, from the bottom of the bedplate to the floor of the 

 bridge above it, is 11 feet 6 inches high. Each generator weighs 

 170,000 pounds, and the revolving part alone weighs 79,000 pounds. 

 In most dynamos the armature is the revolving part, but in this case 

 it is the field that revolves, while the armature stands still. It is note- 

 worthy that if the armature inside the field were to revolve in the 

 usual manner, instead of the field, its magnetic pull would be added to 

 the centrifugal force in acting to disrupt the revolving mass; but as it 

 is the magnetic attraction toward the armature now acts against the 

 centrifugal force exerted on the field, and thus reduces the strains in 

 the huge ring of spinning metal. The stationary armature inside the 



