Tuesday 6 October 2009

Tesla's coil makes the sparks fly


As well as the stationary (but working) exhibits at the Forncett Industrial Steam Museum which we visited a couple of days ago, there were some other interesting things.


Someone - I wish I'd asked his name - brought along a collection of seriously shocking electrical machines, many of which he'd built himself. One of these home made devices was the spectacular Tesla coil, which produces telephone number voltages on the shiny sphere. 500,000V is enough to ionise the air between it and the earthed wire dangling two feet above it. The resulting lightning is straight out of Frankenstein's lab, and suitably crackling and fizzing.


His gadget gallery included a Wimshurst Machine, an example of which was used to make pupils' hair stand on end when demonstrated in physics lessons at my school; a Victorian electric shock machine "for nervous diseases"; a mirror galvanometer which will measure currents as small as .005µA (not much good for checking your boat's alternator output, then); and a Geissler tube rotator.


Still to come: the engine whose power source is a solid fuel stove. No steam is involved.

1 comment:

Vallypee said...

That flash is quite something. I wouldn't like to be in the same room with it...took about a charged atmosphere!