D591(DW): Nikola Tesla (1856-1943) was an electrical engineer and inventor who made many pioneering experiments. The photograph shows burning the nitrogen of the atmosphere. This result is produced by the discharge of an electrical oscillator giving twelve million volts. The electrical pressure, alternating one hundred thousand times per second, excites the normally inert nitrogen causing it to combine with oxygen. The flame-like discharge measures sixty-five feet across. Tesla sits in front of the oscillator.