; but it was invulnerable. There was no denying the fact.
The Cambridge professors had undoubtedly blundered in saying that an
initial velocity of 12,000 yards a second would be enough to carry them
to the neutral point. A velocity of nearly 18,000 yards would be the
very lowest required for such a purpose. They had simply forgotten to
allow a third for friction.

The three friends kept profound silence for some time. Breakfast now was
the last thing thought of. Barbican, with teeth grating, fingers
clutching, and eye-brows closely contracting, gazed grimly through the
window. The Captain, as a last resource, once more examined his
calculations, earnestly hoping to find a figure wrong. Ardan could
neither sit, stand nor lie still for a second, though he tried all
three. His silence, of course, did not last long.

"Ha! ha! ha!" he laughed bitterly. "Precious scientific men! Villainous
old hombogues! The whole set not worth a straw! I hope to gracious,
since we must fall, that we shall drop down plumb on Cambridge
Observatory, and not leave a single one of the miserable old women,
called professors, alive in the premises!"

A certain expression in Ardan's angry exclamation had struck the Captain
like a shot, and set his temples throbbing violently.

"_Must_ fall!" he exclaimed, starting up suddenly. "Let us see about
that! It is now seven o'clock in the morning. We must have, therefore,
been at least thirty-two hours on the road, and more than half of our
passage is already made. If we are going to fall at all, we must be
falling now! I'm certain we're not, but, Barbican, you have to find it
out!"

Barbican caught the idea like lightning, and, seizing a compass, he
began through the floor window to measure the visual angle of the
distant Earth. The apparent immobility of the Projectile allowed him to
do this with great exactness. Then laying aside the instrument, and
wiping off the thick drops of sweat that bedewed his forehead, he began
jotting down some figures on a piece of paper. The Captain looked on
with keen interest; he knew very well that Barbican was calculating
their distance from the Earth by the apparent measure of the terrestrial
diameter, and he eyed him anxiously.

Pretty soon his friends saw a color stealing into Barbican's pale face,
and a triumphant light glittering in his eye.

"No, my brave boys!" he exclaimed at last throwing down his pencil,
"we're not falling! Far from it, we are at present