Ammeter Wattmeter for an alternative use for this instrument. Moving iron ammeters use a piece of iron which moves when acted upon by the electromagnetic force of a fixed coil of wire. The moving-iron meter was invented by Austrian engineer Friedrich Drexler in 1884. This type of meter responds to both direct and alternating currents (as opposed to the moving-coil ammeter, which works on direct current only). The iron element consists of a moving vane attached to a pointer, and a fixed vane, surrounded by a coil. As alternating or direct current flows through the coil and induces a magnetic field
Main Street Electrical Parade Street Electrical Parade was the Electrical Water Pageant, a show made up of fourteen 25-foot-tall (7.6 m) screens with electrical lights placed on them. Not long after the Electrical Water Pageant debuted, Card Walker commissioned the development of what became the Main Street Electrical Parade to provide Disneyland with a similar nighttime visual spectacle. The parade's design used nickel–cadmium batteries, which the Disney movie studio had recently started using, and Italian-made miniature bulbs that Disneyland staff had seen in light displays along Michigan Avenue in Chicago, Illinois. Disney arranged for the parade's original floats to be constructed by Silvestri, the