if a certain number of the gas compartments retained their
charges of hydrogen. There were no fewer than seventeen of these
gas-balloons arranged in a single line within the envelope.
Beneath the hull and extending the full length of the latter was
a passage which not only served as a corridor for communication
between the cars, but also to receive a weight attached to a
cable worked by a winch. By the movement of this weight the bow
or stem of the vessel could be tilted to assist ascent and
descent.

The construction of the vessel subsequently proved to be the
easiest and most straightforward part of the whole undertaking.
There were other and more serious problems to be solved. How
would such a monster craft come to earth? How could she be
manipulated upon the ground? How could she be docked? Upon
these three points previous experience was silent. One German
inventor who likewise had dreamed big things, and had carried
them into execution, paid for his temerity and ambitions with his
life, while his craft was reduced to a mass of twisted and torn
metal. Under these circumstances Count Zeppelin decided to carry
out his flights over the waters of the Bodensee and to house his
craft within a floating dock. In this manner two uncertain
factors might be effectively subjugated.

Another problem had been ingeniously overcome. The outer
envelope presented an immense surface to the atmosphere, while
temperature was certain to play an uncertain part in the
behaviour of the craft. The question was to reduce to the
minimum the radiation of heat and cold to the bags containing the
gas. This end was achieved by leaving a slight air space between