James W. Butler and Edmund Edwards' "Steam Dart" flying machine derived, obviously, from a folded paper plane. What was of interest in their design, was their inclusion of an internal steam engine to move the flying machine through the air by a "... jet of steam or other fluid (which) may act by reaction on the air." This resulted in a remarkably prophetic design, that of a delta-winged jet-propelled aircraft. Alternatively, they also thought a propeller or moving wings might be employed to impart motion. Their design also included the use of trailing edge "horizontal and vertical rudders (to) guide the machine vertically and horizontally." They conceived of a launching apparatus from which the "Steam Dart" could rise once sufficient speed and lift had been generated. This design was awarded Patent #2115 by His Majesty's Patent Office, London, England, in 1867. It seems that no attempt was made to actually build the remarkable machine.