stured to Rick and Scotty. "We know that the source will
not come up over our horizon until about one o'clock. When it does, we
would appreciate your help in making audio recordings. Until then,
you're on your own."

"What'll we do?" Scotty asked.

Rick looked at his watch. It was shortly after nine. "Why not go over to
see the pyramids? Then we can have lunch at the Mena House and come back
in time to go to work."

"Good idea. Better tell Winston, though, in case something comes up."

Rick did so, and the boys went outside to where Hassan waited patiently.
They told him their plans and got into the little car for the short
drive to Giza.

"I got some of that, but not all," Scotty said. "Give me a brief
rundown."

"Okay. I'm no expert, but I think I got the drift. To start with, the
most common thing in space is hydrogen gas. It gives off energy that can
be detected on the 21-centimeter wave length. This is important to the
radio astronomers, because they can use their telescopes to figure out
how hydrogen is distributed throughout the universe."

"I'm with you," Scotty said. "Now our boys have proved that the funny
signals in the hydrogen impulse they've been getting originate in space,
and hydrogen shouldn't act like that."

"That's it. Also, a hydrogen source in space ought to stay fixed. But
this one is shooting off at high velocity. That would be strange enough,
but it's also giving off signals that don't seem natural."

"So the scientists yell for help from their colleagues in America and
England, and perhaps someone can figure out what's causing this strange
behavior?"

"On the button, ol' buddy."

Scotty grinned. "It will probably turn out to be an Egyptian space cat
mewing for milk from the Milky Way."

Rick patted the kitten in his pocket. He had replaced the one turned
over to the intruder the night before. Now, as he told Scotty, only two
orphan kittens needed homes. But placing the kittens didn't answer the
questions that puzzled him. Why was the Egyptian cat important? And who
were the people that wanted it?

There were things about the mystery that didn't add up. For instance,
Fuad Moustafa had written a polite letter claiming the cat, but strictly
impolite and violent efforts had been made to get it. And where were the
brothers Moustafa?

Hassan drew to a stop before the great pyramid of Khufu. "We here. Want
to go in?"

"In a while," Rick answered. "We'll take a look around outside,