FORCE OF A WATER JET.
In order to work successfully the great banks of pebbles and boulders in which gold is found, and to extract front which the fine particles of gold penned up in them the Western miners use a stream of water, which does the work thoroughly, unaided by any force except its own. In many directions, away up on the surrounding hills, sluices and waterways are constructed, so that the various streamlets will send their waters down to a reservoir built somewhere within 300 or 400 yards of the cliff that is to be worked and 100 or 150 feet above it. From this reservoir an iron pipe, varying in diameter from six to twenty inches, according to the work that is to he done, is laid to the working level, the point from which the workmen will direct the stream thus conveyed to them. Here a piece of machinery is built, weighing from one to three tons, with its frame not only securely anchored to the ground, but also weighted down with ten or fifteen tons of rock. It consists of a heavy nozzle jointed to the iron pipe that brings the water from the reservoir. This nozzle is so constructed tnat it may be directed at any part of the cliff by the hands of one man, and yet, if it should get out of the man’s control, and the water is not instantly turned on at the reservoir, it becomes perfectly unmanageable. At the proper moment the sluice-gate at the reservoir is opened, and the water runs with immense force down the iron pipe and out at the nozzle, whose diameter is about eight inches. The pipeman turns the stream on the cliff and pebbles and boulders, some of the latter weighing more than a ton, are knocked down and scattered about. The force of this stream is almost incredible. It has no power behind it but its own gravity, and as it strikes the cliff makes a roar that may be heard for more than a mile. It will wash down more “pay dirt” in one day than 10,000 men could handle with the oldfashioned “rockers.” If a knife blade is exposed to the force of the stream, it will be torn from the handle, and a crowbar will be wrenched from the hands of the strongest man, if he succeeds in getting the point in for the distance of half an inch—the farthest distance that an axe can be driven into it. Sometimes a nozzle will tear itself loose from its fastenings, and. when that happens, the stream deals destruction and death all round it until some one shuts the water off at the reservoir.