ing to combine arrangements to break
the fall. The reader may perhaps remember Ardan's reply to the Captain
on the day of the famous meeting in Tampa.

"Your fall would be violent enough," the Captain had urged, "to splinter
you like glass into a thousand fragments."

"And what shall prevent me," had been Ardan's ready reply, "from
breaking my fall by means of counteracting rockets suitably disposed,
and let off at the proper time?"

The practical utility of this idea had at once impressed Barbican. It
could hardly be doubted that powerful rockets, fastened on the outside
to the bottom of the Projectile, could, when discharged, considerably
retard the velocity of the fall by their sturdy recoil. They could burn
in a vacuum by means of oxygen furnished by themselves, as powder burns
in the chamber of a gun, or as the volcanoes of the Moon continue their
action regardless of the absence of a lunar atmosphere.

Barbican had therefore provided himself with rockets enclosed in strong
steel gun barrels, grooved on the outside so that they could be screwed
into corresponding holes already made with much care in the bottom of
the Projectile. They were just long enough, when flush with the floor
inside, to project outside by about six inches. They were twenty in
number, and formed two concentric circles around the dead light. Small
holes in the disc gave admission to the wires by which each of the
rockets was to be discharged externally by electricity. The whole effect
was therefore to be confined to the outside. The mixtures having been
already carefully deposited in each barrel, nothing further need be done
than to take away the metallic plugs which had been screwed into the
bottom of the Projectile, and replace them by the rockets, every one of
which was found to fit its grooved chamber with rigid exactness.

This evidently should have been all done before the disc had been
finally laid on its springs. But as this had to be lifted up again in
order to reach the bottom of the Projectile, more work was to be done
than was strictly necessary. Though the labor was not very hard,
considering that gravity had as yet scarcely made itself felt, M'Nicholl
and Ardan were not sorry to have their little joke at Barbican's
expense. The Frenchman began humming

"_Aliquandoque bonus dormitat Homerus,_"

to a tune from _Orphee aux Enfers_, and the Captain said something
about the Philadelphia Highway Commissioners who pave a stree