The mining activity, however, brought about a remarkable expansion in the iron road, which pushed inland for nearly 600 miles. Then the water question became one of vital importance, because the locomotives required copious and frequent drinks to slake their tremendous thirsts. To bring this article up from the coast was costly. The scanty rainfall was collected so far as possible by impounding, but the water thus secured was found to be useless for the railway’s purposes. It became so heavily charged with deleterious substances, as it flowed over a salt-impregnated soil, that it set up heavy incrustation in the boilers. This was a serious drawback, because it reduced the life of the engine’s internal organs very materially, and militated against the iron horse’s efficiency. To remedy this state of affairs, the earthen dams constructed at various points along the route, which formed small reservoirs, were supplemented by condensing plants. The most notable installation of this description was completed at Coolgardie. This plant was designed primarily to utilise the salt water from the adjacent mines. The Coolgardie condenser was capable of supplying about 60,000 gallons of fresh water per day, at a cost of 37_s._ 6_d._, or say $9 per 1000 gallons, and to furnish this requirement entailed an expenditure of £15,000, or $75,000, on the apparatus. A large distilling apparatus was set up also at Geraldton to supply the Northern railway running into the Murchison gold-fields, where the water question was also a serious factor. [Illustration: THE ENTRANCE TO THE TUNNEL, 1,096 FEET LONG, THROUGH THE DARLING RANGE This is the only tunnel on the West Australian Government Railways.] While this palliative met the situation up to a certain point, it was far from satisfactory. Consequently, a few years ago a huge project was evolved to supply the Coolgardie gold-fields with unlimited quantities of excellent water. A large dam was thrown across a rift on the western slope of the Darling range about 20 miles from Perth, whereby 4,600,000,000 gallons of water are banked up. The water is dispatched from this reservoir to the gold-fields 350 miles away through a pipe 30 inches in diameter, which is sufficient to ensure the inhabitants in the gold country receiving a steady and continuous supply of 5,000,000 gallons per day. At intervals along the line large intermediate tanks are provided, together with pumping plants. As the pipe-line runs alongside, and the pumping stations are situate beside the railway, the latter can now secure ample supplies of pure water, so that the Eastern Gold-fields railway is concerned no longer with troubles in this direction. [Illustration: THE DEARTH OF SUITABLE WATER WAS THE SERIOUS PROBLEM IN THE EARLY DAYS OF THE COOLGARDIE GOLDFIELDS. AS THE RAILWAY COULD NOT HAUL SUPPLIES FROM THE COAST, THIS NOVEL CONDENSING PLANT WAS ERECTED