Mike, the black color of vacuum tubing is from carbon black powder, the same stuff that makes tires black. Some types of hose have enough carbon in them to conduct high voltage, especially if the coil wire is pretty short. It would have had a BAD miss under load.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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