ely separated points, though one of them said there were
three pillars of fire and that these looked more like the beams of
powerful search-lights. All agreed on the terrific roar. And, after all,
these two liners did disappear. There must be something quite out of the
ordinary about the way in which they were captured or destroyed, and
this occurrence may well be supposed to have a bearing on the matter."

"Possibly they were destroyed by some freak electrical storm," I
suggested.

"Where then are the wrecked vessels?" asked Hart. "No, Jack, electrical
storms do not destroy huge air liners and then suck them out into space
beyond our vision. These two ships are no longer on the surface of the
earth, else they would have been long since located. The magnetic
direction finders of the transportation people have covered every inch
of the United States, as well as Mexico and Canada."

"Of course they might have been carried halfway around the world by a
wind of unprecedented velocity." I commenced a silly argument in favor
of the theory that the elements had accounted for the two vessels, but
was interrupted by the mounting roar of great engines throbbing
overhead.

"Hurry up there, George!" shouted Hart. "It's the SF-22 coming in. We
have to be ready for the take-off in five minutes!"

* * * * *

He hastened to take George's place at the washbowl and all was activity
within the confines of our hangar. George and I left the office and went
out to the landing field, which was now brilliant with the glare of
floodlights. The _Pioneer_ had been trundled into the open and stood
ready for the flight. Not a hundred feet above the field, the huge
silver moth that was the SF-22 swept by in a wide circle that would
bring her into the wind. The roar of her engines died as she swung out
of the circle of light into the surrounding darkness.

The crowds which had gathered to witness her landing buzzed with excited
comment and speculation. Her nose brought slightly up, she dropped to a
perfect three-point landing, the brakes screeching as she was brought to
a standstill at the hangar of the transportation company.

"Come on now, you fellows," came the voice of Hart Jones from the hangar
entrance, "there's no time to lose. The _Pioneer_ takes off immediately
after the big fellow."

We hurried to the waiting ship, which seemed like a tiny toy when
compared with the giant SF-22. I had observed very l