The celebrated Harry W. Tinder, whose name we mentioned at the
beginning of this story, had been engaged as aeronaut. He had no
assistant, and the only passengers were to be the president and
secretary of the Weldon Institute.

Did they not merit such an honor? Did it not come to them
appropriately to rise in person to protest against any apparatus that
was heavier than air?

During the seven months, however, they had said nothing of their
adventures; and even Frycollin had not uttered a whisper of Robur and
his wonderful clipper. Probably Uncle Prudent and his friend desired
that no question should arise as to the merits of the aeronef, or any
other flying machine.

Although the "Go-Ahead" might not claim the first place among aerial
locomotives, they would have nothing to say about the inventions of
other aviators. They believed, and would always believe, that the
true atmospheric vehicle was the aerostat, and that to it alone
belonged the future.

Besides, he on whom they had been so terribly--and in their idea so
justly--avenged, existed no longer. None of those who accompanied
him had survived. The secret of the "Albatross" was buried in the
depths of the Pacific!

That Robur had a retreat, an island in the middle of that vast ocean,
where he could put into port, was only a hypothesis; and the
colleagues reserved to themselves the right of making inquiries on
the subject later on. The grand experiment which the Weldon Institute
had been preparing for so long was at last to take place. The
"Go-Ahead" was the most perfect type of what had up to then been
invented in aerostatic art--she was what an "Inflexible" or a
"Formidable" is in ships of war.

She possessed all the qualities of a good aerostat. Her dimensions
allowed of her rising to the greatest height a balloon could attain;
her impermeability enabled her to remain for an indefinite time in
the atmosphere; her solidity would defy any dilation of gas or
violence of wind or rain; her capacity gave her sufficient
ascensional force to lift with all their accessories an electric
engine that would communicate to her propellers a power superior to
anything yet obtained. The "Go-Ahead" was of elongated form, so as to
facilitate her horizontal displacement. Her car was a platform
somewhat like that of the balloon used by Krebs and Renard; and it
carried all the necessary outfit, instruments, cables, grapnels,
guide-ropes, etc., and the piles and accumulators f