I wound the primary coil and finished all the wiring except for the spark gap and 12v power supply. I also wound the secondary but have yet to photograph it.
Monday, March 22, 2010
Monday, March 15, 2010
I just finished building Franklin's Bells. The bells and hardware are all brass. The terminals are vintage as are the Bakelite standoffs used for the base of the bells and the terminals.
Electrostatic bells like these are often referred to as Franklin's Bells, after the eminent American scientist Benjamin Franklin, who installed them in his house to warn him of approaching thunderstorms, as is recorded in a famous portrait of Franklin observing his set of electrostatic bells as a thunderstorm raged outside. This electrostatic device actually was invented in about 1742 by Andrew Gordon, Professor of Natural Philosophy at the University at Erfurt, Germany. Gordon's Bells constituted the first device that converted electrical energy into mechanical energy in the form of continuous mechanical motion, in this case, the moving of a bell clapper back and forth between two oppositely charged bells.
Franklin made use of Gordon's idea by connecting one bell to a pointed rod attached to his chimney and a second bell to ground. This pointed rod discharged electrical energy from heavily charged passing clouds that would cause Franklin's set of Gordon's Bells to ring.