Nevertheless, they had appliances which seemed to run on electricity, or some equivalent to it.  Since he’d gotten a tingle when he unintentionally stuck his fingers inside the heart monitor, it implied that the power came from the air, somehow and was focused in the appliance.  Tesla had proposed that such a thing was possible, but had never built a functional prototype.  On the other hand, it was hard to argue with the proof on the table beside him.  However they did it, it worked.