Dr. Albert Langston designed and developed the Aether Displacer. The LLAD is a marvel of anthracite coal burning technology that uses the Aether knots and breaks in the coal and uses a white fire distilling technique in the furnace to produce more energy than is normally produced from burning coal.
The LLAD has been modified over the years to include additional clockwork machinery to include the perpetual motion machine, tesla coils and the combustion engine. These devices when coupled together in a seemingly endless array of means, are able to generate ample force to create air stream bubbles and current filters thereby allow for the movable fortresses on the land and air as well as Aether travel to other planets.
The LLAD and the early contributions of Dr. Langston should never be forgotten else all is lost and we will surely go back to the Dark Ages when men relied on animals instead of their own ingenuity to get them from place to place.