Tesla maintained that only
one end of his lamps needed to be connected to the supply if the rate of
change was sufficiently high. This is demonstrated above.
The energy which has energized the lamp has passed through space (not through a wire). The actual current flowing through the fluorescent tube is very low (around 6 µA) although the light was shining clearly.
By also connecting the other end of the tube to the TBU12V25KHz the light intensity increased ten fold, but the current consumption increased 8300 times to 50 mA.
We have experimented with a number of different ways to excite a fluorescent tube and found that light-output to power-output can be increased considerably.
Make your own experiments with high rate of change (TBU12V25KHz) and light.