HYDRAULIC ENGINEERING EXTRAORDINARY.

Grey River Argus, Volume XV, Issue 1899, 7 September 1874, Page 3

HYDRAULIC ENGINEERING EXTRAORDINARY.

Under the above title an article appeared in the " Engineer," of April 3, which we reproduce, as it may prove useful in the present unsettled condition of the great question of our water supply :— An iron conduit has recently been constructed, which, according to the "Mining and Scientific Press," sustains the greatest water pressure in the world, namely, 1720 ft, or 7501 b to the square inch. It carries the water supply of Virginia City and Gold Hill, Nevada, from Narlette Lake, situated on an elevation of about 1500 ft above the former town, over a valley seven miles in width, the sides of which are steep and precipitous, and through a route presenting engineering difficulties of an unusually troblesome nature. The most awkward feature of the undertaking begins at an elevation of 1885 ft above the track of the Virginia and Trucke Railroad, at a point about two miles west of Lake View Toll-house, and thence follows by an easterly course the crest of the spur from which it starts, crosses the valley at the toll-house referred to, and gradually ascends to its outlet end, making the entire length 37,100 ft. The water at present is taken from Dall's Creek by an 28-inch flume four miles long, to the inlet, or western end of the pipe the water is conveyed through a flume of the same size, 9 miles long, into Virgina and Gold Hill, where it connects with the present city pipe system. In the future the water from Marlette Lake will be conveyed to the inlet of tbe pipe, and be added to the supply from Dall's Creek. All the iron pipe is coated, inside and out, with a mixture of asphaltum and coal tar, thoroughly boiled together, each separate piece being plunged and rolled about in a bath of this mixtureforfrom seven to ten minutes before being shipped to its destination. The average diameter of the pipe is 11 £in., and its entire weight about 700 tons. Nearly one million rivets were used to manufacture it, and some 35 tons of lead were required in making the joints. At the point of heaviest pressure the irou is No. 0 thick, and is hot riveted with fin. rivets, there being a double row on the straight seam, and a single row on the round seam. The pressure gradually decreases as the ground rises to the east and west, and the iron decreases in thickness from five-sixteenths to one-sixteenth of an inch towards both inlet and outlet. But on its course to the outlet, it having to cross a great many spurs and sags, the iron varies of course according to the pressure. This inlet has a perpendicular elevation above the outlet of 465 ft, but just now only 300 ft are used, as this head will supply ten times as much as the two towns has hithertofore had. This head carries into Virginia about 2,000,000 gal every twenty-four hours ; and by increasing the head to its fullest capacity, the supply can be Increased to 2,350,000 gal per day. From the time of commencing the manufacture of the pipe until the water ran into Virginia City only five months elapsed, ending in August last. Theßisdon Iron and Locomotive Works constructed the pipe, and the credit of accomplishment of the undertaking is due to the engineer, Mr Heiman Schussler. It is difficult to say which characteristic of our Western engineers is the most remarkable, the courage with which thej attack the most stupendous and difficul problems, or the promptitude and celeritj with which they carry out their ideas There is a great future- for a county which produces such men and sue! achievements.