Hydro-Electric Machine

Device for generating electricity by the pa age of water vapor through narrow orifices. The fact was accidentally discovered by a workman. Sir W. Armstrong, while investigating the phenomenon, ascertained that the vapor was positively charged, and that the ve el from which it i ued, if insulated, was negatively charged. Faraday afterward found out the cause of the action; viz., the a bleaching agent, in medicine, surgery and in the laboratory. It evolves 475 volumes of oxygen when warmed. Under the name of Golden Fluid, a solution of it is sold for bleaching the hair. H2O, was discovered by The nard, 1818.