Tesla ? coil

From:  TYR580 [SMTP:RKoonce-at-tyler-dot-net]
Sent:  Monday, June 01, 1998 6:10 PM
To:  Tesla List
Subject:  Tesla ? coil

Some time ago I visited the Science Place museum at Dallas Fair Park and
witnessed the "Electric Show".  There was a demonstration of a large
VanDe Graf generator (very impressive) and a coil quite unlike a
conventional Tesla coil.  It was a orizontally- mounted ~3 ft. diameter
coil which tapered to a ~4" disk from which the discharge (6-8 feet
long) emanated.  The controller apparently had a rotary gap (completely
enclosed).  The only connection from the controller to the coil was by
two thick cables.  Does anyone have an idea what type of coil this is?

Thanx, Raymond Koonce