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Show 1 2 6 0 REPORT OF THE CHIEF OF ENGINEER8. possible that, with the present engine- force, which now makes no permanent headway against the water, the water may be raised to the tunnel- level and ran off through it to the Carson River. At any rate, it will ver. y much facilitate the keeping down of the water and will afford a new foundation 1,900 feet below the surface from which t o work As with the Savage, so with the other mines which are much troubled with water; when the tunnel or one of its branches reaches them, it will take off the water which comes in above the tunnel- level, and will lessen very much the work of pumping oat that which comes in below. It will also greatly assist in ventilation ; but in regard to its merits in thi6 respect I am unable to speak. As regards the feasibility of using the tuunel for the extraction of ore, it admits of discussion, and can only be decided when the time comes. The ore now, after being hoisted, is taken from the shaft, and in some instances, as the Bonanza Mines, is milled very near the mine; in others, it is hauled in wagons to various distances from one to three or four miles, and in others still it is taken by the railroad to the mills along the Carson a distance of from 12 to 15 miles. If the ore when taken from the tunnel-month should be conveyed to the present existing mills and reduced, it would unquestionably be more expensive than now; but if new mills should be built near the tunnel- month and run by the tunnel- water, or built on the banks of the Carson River, just below, iu my opinion the ore could be reduced at a much lower cost than at present, aud the ore which now is too poor to work or which barely pays for milling might be mad « to pay a good profit. The capacity of the tunnel of course would be limited; bnt with a double track, and care and economy in its service, it would probably meet all the demands upon it. Situated, as tbeComstock is, in the midst of a dry, totally- unproductive desert, over 6,000 feet above sea- level, on the side of a mountain, needing and using vast quantities of supplies of various kinds, it may not be wholly uninteresting or uninstruotive to inquire as to the nature and source of these supplies, and the methods of getting them to their destination. One of the first wants felt by the pioneers of the Comstock was water, and it was procured in very limited quantities from a few springs in the vicinity. As the lode became more and more developed, the mines and mills and the gathering people demanded more and more water, and the want of it was severely felt. The mills sunk shafts and drifted for water, and a good deal was obtained from the tunnels driven into the mountains in search of the precious metals. A company was finally formed for the purpose of gathering and furnishing water, and their supply was chiefly obtained from the prospecting tunnels and conducted in pipes about Virginia City and Gold Hill. Bat the supply was still far from sufficient and the quality very bad, and the company finally achieved a great triumph in hydraulic engineering by bringing to the cities of the Comstock an abundant supply of fresh and clear mountain water from the summit streams and lakes of the Sierras. The water is now taken from Dall's Creek, in the Sierras, bnt the company are extending their flume to tap Marietta's Lake, from whence nearly all the water will be taken. This lake is 1,600 feet above Virginia City and within a mile of Lake Tahoe. The water will be conducted in a wooden flume in a northerly direction for about 5 miles, then, passing under the mountains through a tunnel nearly a mile long, it pursues its wiuding way iu a flume for 6 miles, when it reaches the point where it becomes necessary to make the descent into the Washoe Valley below. There it is received into a double line of iron pipes, which conduct it down to and across the valley and up the opposite mouutain. The pipes are, one, 12 inches in diameter and riveted with f inch bolts. It is^- inch thick at the lowest point, where the pressure is greatest, and tapers from this point to the entrance and exit, where it is only ^- iuch thick. The other is a 10- inch pipe, lap- welded, and of uniform thickness. From the point of entering the pipe the water makes a descent of 1,963 feet in a horizontal distance of 1^ miles into Washoe Valley. There it commences to ascend until it reaches a point 1,498 feet above the lowest point, at a distance of 6 miles from it. Here it is again received into a flume, and is conducted circling about the mountain- slopes a distance of about & miles, until it reaches its destination. The flume has a fall of 1 foot to each 44 feet horizontal distance. The amount supplied now is about 3,000,000 gallons daily, but its capacity, when fully completed, will be more than 10,000,000 gallons daily. The mines and mills devour a vast amount of fuel and lumber. In that volcano-formed land there is no coal, and the fires must be fed with wood. All the wood which grew about the Comstock was used up long ago, and now, as before in the case of water, it is the Sierras which furnish the supply. This is taken from the great basin about Lake Tahoe, and from the eastern summits above Huftaker's, and is brought down the mountains in flumes, which are gradually extended backward as the supply is exhausted. There are saw- millsou the mountains at which is cut the square timber and the lumber used in the mines and in the cities. The flumes are so constructed that timber 40 feet loug can be sent down. The wood and lumber when it reaches the valley is mostly taken by the Virginia and Truckee Railroad, and conveyed to the places where it is to be used. Immense quantities of wood are also floated down the Carson River to Empire, Dayton, and Satro, and it is estimated that at least 250,000 cords of wood |