Hydroelectric Machine

( Electric.) A machine invented by W. Armstrong, consisting of a steam boiler, insulated by means of strong gla pillars, on which it rests. Attached to the upper part of the boiler, a large number of bent iron tubes, terminating in wooden jets, allow the steam to pa out with considerable force. A conductor projects from the boiler, terminating in a knob, while in front of the bent tubes is a metallic case, containing several rows of points for carrying off the opposite electricity of the steam. It has been shown by Prof. Faraday that the electricity generated by this machine does not depend on the i ue of steam through small orifices, nor on any chemical or physical change due to evaporation or condensation, but is merely the result of the friction of the water particles which are driven through the jets by the steam. These particles act similarly to the gla plate in the ordinary machine, and give out positive electricity, while the wooden jets and pipes act as rubbers, and give out negative electricity. The true source of electricity in the machine is in fact the friction of the steam, the boiler being negative and the escaping vapor positive. The best material for the orifice of the jet appears to be wood, while ivory is one of the worst. A small quantity of oil or turpentine in the exit-pipes produces a remarkable change in this machine, - the electrical states become reversed, the boiler being positive and the steam negative. The H. E. machine is a powerful source of electricity.