es!"

The second assistant was galvanized into activity, and upon a screen
before him there appeared a view as though he were looking directly
upward from the prow of the great vessel. The air above them was full of
aircraft of all shapes and sizes, and occasionally the image of one of
that flying horde flared into violet splendor upon the screen as it was
caught in the mighty, roving beam of one of the twelve ultra-light
projectors under test.

"Upper lights and lookout plates--all x," the second assistant reported,
and other assistants came to attention as the check-out went on.

"Lower lights and lookout plates!"

"All x," was the report, after each of the twelve ultra-lights of the
stern had swung around in its supporting brackets, illuminating every
recess of the dark depths of the bottom well of the berth and throwing
the picture upon another screen in lurid violet relief.

"Lateral and vertical detectors!"

"Laterals XP2710--all x. Verticals AJ4290--all x."

"Receptors!"

"15,270 kilofranks--all x."

"Accumulators!"

"700,000 kilofrank-hours--all x."

Having thus checked and tested every function of his department,
Breckenridge plugged into "Captain," and when the green light went on:

"Chief pilot check-out--all x," he reported briefly.

"All x," acknowledged the speaker, and the chief pilot unplugged.
Fifteen minutes remained, during which time one department head after
another would report to the captain of the liner that everything in his
charge was ready for the stupendous flight.

"All x, Steve?" Breckenridge turned to the computer. "How do you check
acceleration and power with the observatory?"

"Not so good, old bean," the younger man frowned in thought. "They
figure like astronomers, not navigators. They've made no allowances for
anything, not even the reversal--and I figure four thousands for that
and for minor detours. Then there's check station errors...."

"Check-station errors! Why, they're always right--that's what they're
for!"

"Don't fool yourself--they've got troubles of their own, the same as
anybody else. In fact, from a study of the charts of the last few weeks,
I'm pretty sure that E2 is at least four thousand kilometers this side
of where he thinks he is, that W41 is ten or twelve thousand beyond his
station, and that they've both got a lateral displacement that's simply
fierce. I'm going to check up, and argue with them about it as we pass.
Then there's another thing