Harry Goldman made my day a few years ago when he xeroxed this wonderful article for me:
Nikola Tesla - Electrical Oscillators - Electrical Experimenter July 1919
http://www.electrotherapymuseum.com/2006/ElectricalOscillators/index.htm (http://www.electrotherapymuseum.com/2006/ElectricalOscillators/index.htm)
I spent a month or two and made some renderings of some of the coils, seen below.
I believe a lot can be learned if these circuits can one day be reproduced accurately.
(My philosophy in recreating Tesla's work is to start from the beginning...)
Perhaps some of us machinists can work together in the future and put our efforts into recreating some of them.
I am working towards getting our foundry back up and running, but we're limited to lower melting compositions as bronze and brass...Does anyone out there have iron casting capabilities, or use of CNC for a good cause?

Jeff

(http://www.electrotherapymuseum.com/2006/TeslaOscillators1Color/thumbnails/TeslaOscillator1.jpg)
(http://www.electrotherapymuseum.com/2006/MercuryBreak609251/thumbnails/01-609251.jpg)
(http://www.electrotherapymuseum.com/2006/MercuryBreak609251/thumbnails/609251-01.jpg)
(http://www.electrotherapymuseum.com/2006/MercuryBreak609247/thumbnails/GapAssem1-11.jpg)

(http://www.electrotherapymuseum.com/2006/MercuryBreak609247/thumbnails/GapAssem1-09.jpg)
(http://www.electrotherapymuseum.com/2006/MercuryBreak609247/thumbnails/GapAssem1-01.jpg)
(http://www.electrotherapymuseum.com/2006/MercuryBreak609248/thumbnails/Untitled-14.jpg)
(http://www.electrotherapymuseum.com/2006/MercuryBreak609248/thumbnails/Untitled-6.jpg)

(http://www.electrotherapymuseum.com/2006/IgnitionTesla609250/thumbnails/Untitled-8.jpg)
(http://www.electrotherapymuseum.com/2006/MiscOscillators/thumbnails/TeslaOscillatorFig7.jpg)
(http://www.electrotherapymuseum.com/2006/MiscOscillators/thumbnails/TeslaOscillatorFig4.jpg)
(http://www.electrotherapymuseum.com/2006/Figure1/thumbnails/Fig1-01.jpg)

(http://www.electrotherapymuseum.com/2006/583953/images/583953-1.jpg)