mitter, batteries, and
command circuits that could be triggered from the ground. It was a
highly complex and beautifully engineered package for receiving data,
storing it, then retransmitting it.

"But why?" Rick demanded. "Why send up a rockoon at all? What data does
it receive and transmit, and what do the people at the mansion do with
it?"

"What Rick is asking," Scotty observed, "is the question that has
puzzled us since we got here. Why do the stingarees fly?"

Steve waved a hand. "Patience for just a few more minutes. Anything
else, Cobb?"

The electronics expert shook his head. "Not unless you have specific
questions. In summary, this is a very elegant little assembly of
receiver, data recorder, transmitter, and command circuits."

"Fine. McDevitt, what about the rocket?"

The man from Wallops Island shrugged. "Nothing very complex about it.
It's a simple solid-fuel rocket with star grain, fired by a squib that
is commanded from the ground. A squib is simply an igniter to start the
fuel burning. Battery power makes it glow red hot when turned on."

"How high an altitude would the rocket reach?" Steve asked.

"It's difficult to be precise, but I'd estimate the balloon carries it
to ten thousand feet, then it is fired by signal from the ground at the
proper time. The rocket would go to about one hundred thousand feet,
plus or minus twenty thousand. In other words, I'd guess its maximum
altitude at nearly twenty-three miles."

"Did you say fired at the proper time, or proper altitude?" Rick asked
quickly. He wanted clarification of the point, although he was sure
McDevitt had said "time."

"The altitude isn't important. I'd say time was the principal factor."

"But if altitude isn't important, why use a rockoon? Why not use a
rocket launched directly from the ground?" Scotty demanded. He looked
puzzled.

Rick looked at Steve expectantly. The young agent smiled. "Got the
answer, Rick?"

"Maybe. It's a matter of secrecy, isn't it? The folks around here were
puzzled by the flying stingarees, but they would have been more puzzled
by rocket firing. They'd have been curious enough to want to know why
the rockets were being fired, and it's certain that an investigation
would have resulted. By using rockoons, with balloons that didn't look
like balloons, Camillion confused the issue. People who reported seeing
things got laughed at, mostly because they call any unidentified flying
object a flying saucer. Th