ing them over carefully. He went
over them again. Not a single one could be repaired at all.

Then he rechecked his velocity figures, hoping against hope that he'd
made a mistake somewhere, dropped a decimal point or forgotten to divide
by two. Anything. Anything!

But there was nothing. His figures had been accurate the first time.

For a while, he just gave up. All he could think of was the terrible
blaze of heat that would wipe out Earth when the Rats set off the sun.
Man might survive. There were colonies that the Rats didn't know about.
But they'd find them eventually. Without Earth, the race would be set
back five hundred--maybe five thousand--years. The Rats would would have
plenty of time to hunt them out and destroy them.

And then he forced his mind away from that train of thought. There had
to be a way to get there on time. Something in the back of his mind told
him that there _was_ a way.

He had to think. Really think.

* * * * *

On 7 June 2287, a signal officer on the Earth destroyer _Muldoon_ picked
up a faint signal coming from the general direction of the constellation
of Sagittarius. It was the standard emergency signal for distress. The
broadcaster only had a very short range, so the source couldn't be too
far away.

He made his report to the ship's captain. "We're within easy range of
her, sir," he finished. "Shall we pick her up?"

"Might be a Rat trick," said the captain. "But we'll have to take the
chance. Beam a call to Earth, and let's go out there dead slow. If the
detectors show anything funny, we turn tail and run. We're in no position
to fight a Rat ship."

"You think this might be a Rat trap, sir?"

The captain grinned. "If you are referring to the _Muldoon_ as a rat
trap, Mr. Blake, you're both disrespectful and correct. That's why we're
going to run if we see anything funny. This ship is already obsolete by
our standards; you can imagine what it is by theirs." He paused. "Get
that call in to Earth. Tell 'em this ship is using a distress signal
that was obsolete six months ago. And tell 'em we're going out."

"Yes, sir," said the signal officer.

It wasn't a trap. As the _Muldoon_ approached the source of the signal,
their detectors picked up the ship itself. It was a standard lifeboat
from a battleship of the _Shannon_ class.

"You don't suppose that's from the _Shane_, do you?" the captain said
softly as he looked at the plate. "She's the