One of the scientific experiments documented by Sir Francis Bacon was a levitating machine. The machine was a wooden tube with metal strings attached to it, around which fit another wooden tube with metal strings attached to the inside of it. The center tube was supposed to spin and by sympathetic vibration cause the strings on the outer tube to vibrate. The resonance from the striking would create a force field, which would levitate the outer tube off of the ground. Colonel Fabyan hired Bert Eisenhour, an engineer from Chicago, to construct this machine at Riverbank. Though the machine was constructed, it did not work. Eisenhour was convinced that the strings were not tuned properly, and suggested they consult someone knowledgeable in acoustics.