Egg of Columbus/Extended operation

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "davep by way of Terry Fritz <twftesla-at-qwest-dot-net>" <davep-at-quik-dot-com>

Tesla list wrote:
> 
> Original poster: "Wade B AndB Anderson by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <nabedaw-at-juno-dot-com>
> 
> Hi guys,

>    First off, Terry, I still haven't been able to find any "decent" info
> on the egg of columbus, I'm open to suggestions???*

	I've not got references handy.  Its nought to do with
	Tesla Coils, as such, if i recall.  I vaguely recall:
		establish a multiphase, reasonably powerful
		magnetic field _axial_ (out the end of a pole piece)
		An 'egg' of iron will then stand on end (ala Columbus
		in the story) and rotate, as it's the 'rotor' of
		a not very efficient induction motor.  Illustrates
		Tesla's Polyphase motor.
	(I disrecall if it works on single phase.  I think yes, but
	needs to be 'hand started'???)
 
>  Secondly, how long can the TC's run before the heat in the spark gap,
> (whether it be rotary or otherwise) force you to shut them down???

	Depends entirely on the spark gap design.  If designed to
	run for extended purposes (mostly: cooling) they will...

	best
	dwp