Obviously, it would greatly economize the capital expenditure to develop the power in one or more central stations by turbines of large size, of uniform type, under common manage ment. It would equally facilitate the sale of the power if manufacturers could take it in any required quantity, without the trouble of sinking wheel pits or erecting turbines. Once given the means of conveying and distributing power instead of water, a very import ant extension of the original project becomes possible. In addition to supplying manufac tures attracted to Niagara, the power may be taken to existing manufactures in Buffalo and Tonawanda.
Various systems of power distribution to different consumers have been tried during the last twenty or thirty years. Quite recently great success has been achieved in some of these systems, and a very short account of the methods adopted will serve to indicate both the nature of the problem at Niagara, and the extent to which past experience affords guidance in its solution.
The Interaational Xiagara Commission.—To secure impartial examination and compe tent discussion of projects for the utilization of Niagara, an International Niagara Commis sion was formed, and a sum of £4,500 was placed in the hands of the commission, to be awarded, partly in premiums to all invited engineers who sent in plans of sufficient impor tance, partly in prizes to those projects judged to be of the highest merit. The commission was constituted as : Sir William Thomson, F.R.S., LL.D., President; Dr. Coleman Sellers, M. Inst. C. E.; E. Mascart, Membre de l'Institut, Paris ; Col. Theodore Turrettini, director of the works for the utilization of the motive power of the Rhilue at Geneva ; Prof. W. C. Unwin, F.R.S., Secretary.
For the information of the competitors, plans and photographs were prepared, and a detailed letter of instructions was drawn up. Competitors were asked to prepare plans and estimates for developing an effective power of 120.000 horses by hydraulic machinery, and for the transmission and distribution of this power partly to a manufacturing district on the land of the company. partly to Buffalo and Tonawanda. The arrangements adopted were success ful. A large number of projects were received from mechanical and electrical engineers of the greatest reputation. Many of these were worked out with extraordinary care and com pleteness. In some cases the accompanying memoir formed a scientific treatise, and con tained information of the greatest value. The following is a Te8•21112i of the projects received : The prizes were awarded as follows for projects comhining the development of power and its distribution : First prize not awarded. One second prize, to the Four of Messrs.
Faesch F Piccard. Geneva. and Messrs. Cuenod Sautter & Co., Geneva. our third prizes, to the projects of Mr. A. llillairet and Mr, Bouvier, Paris ; Mr. Victor Popp. Paris. and
Prof. Hiedler, Berlin ; Prof. L. Vigreux. and Mr. L. Levy, Paris : the PeItou Water Wheel CO,, San Francisco, Cal, and Norwalk Ironworks Co., South Norwalk, Conn. For pro jects for the hydraulic development of the power, prizes were awarded as follows : First prize, to the project of Messrs. Esther Wyss & Zurich. Two second prizes, to the projects of Messrs. Ganz & Co., Budapest ; Prof. A. Lupton. Leeds, and Mr. J. Sturgeon. For projects for the distribution of the power, no prize awarded.
The Tunnel.—Since the invention of machine drills, the question of drilling for the excavation of rock tunnels has become subordinate to the question of the removal of " muck " (broken rock) when rapid driving is required. It is necessary that very little time be lost before and after firing the blasts, so that the muckers can work the longest possible time. To attain this end, powder must be selected which is free of obnoxious gases, and run ways for barrows or cars must be arranged so as to require but one handling of material.
The plate shows method in use during construction of Niagara Falls power tunnel. Here the tunnel was driven in two benches, or, more correctly, one heading and one bench. Muck was taken directly from the heading in cars and dumped into ears on lower floor of tunnel, without interrupting the working of the lower bench. This is the usual practice DOW, when driving tunnels over 10 ft. in height. Several modes of supporting the runways, however, have been used, but we know of none so perfectly adapted to saving of time as mode shown in sketch. In timber section the hangers were put in about 8 ft. apart. The tongs were made of Li in. x in. Norway iron, steel pointed. Rods were 1 in. in diameter, with hooks at both ends ; the bars were of wood, 8 in. x 8 in. 2 in. x 12 in. planks, 24 ft. long, were used for the bridge or floor, on which a track, fastened together at proper gauge, was laid. The advantage of this scaffold was that it was easily put up, and that it did not require to be taken down when blasting the bench. When blasts were made, the planks which connected the upper bench with the first bar were pulled back onto the bench, leaving the balance of scaffold free to swing in any direction. After the blast the planks were run out into place, and the time lost was hardly noticeable. While the scaffold was in use it was necessary to keep it from swaying from side to side. This was done by using iron rods fastened to eyes, bolted to the bars, so that they could he extended to projecting points on side of tunnel. One of the headings where these scaffolds were used was through hard limestone, which broke with sharp cutting edges. Eight bars were used from start to finish.