As in the Porpoise and Monarch, electricity formed the motive power
and was also used for many other purposes on board. Engines operated
by gas produced the current which heated, lighted and moved the ship,
as well as played a part in producing the wonderful gas.

The ship moved forward or backward by means of a novel arrangement.
This was by the power of compressed air. From either end of the lower
hull there projected a short pipe working in a ball and socket joint,
so it could be turned in any direction. By means of strong pumps a
current of compressed air could be sent out from either pipe. Thus
when floating above the earth the ship was forced forward by the blast
of air rushing from the pipe at the stern. It was the same principle
as that on which a sky rocket is shot heavenward, save that gases
produced by the burning of powder in the pasteboard rocket form its
moving impulse.

In the case of the Flying Mermaid, it could be made to move backward
by sending the air out of the forward tube. Thus, when in the water,
the compressed air rushing from the pipe struck the fluid and forced
the ship forward or backward as was desired. It floated on the
surface, the deck being about three feet out of water, while the
aluminum gas bag was overhead.

The engine room was a marvel of machine construction. It contained
pumps for air and water, motors, dynamos, gas engines, and a maze of
wheels and levers. Yet everything was very compact and no room was
wasted.

The use of the air method of propulsion did away with the necessity of
a large propellor such as most airships have to use, a propellor which