ach
other's faces. Thorvald's was bleak, hard, his eyes on the stream behind
them as if he expected at any moment to see a Throg emerge from the
surface of the water.

"Suppose that thing--" Shann pointed upstream with his chin--"follows
us? What is it anyway?" Hound suggested Terran dog, but he couldn't
stretch his imagination to believe in a working co-operation between
Throg and any mammal.

"A rather spectacular combination of toad and lizard, with a few other
grisly touches, is about as close as you can get to a general
description. And that won't be too accurate, because like the Throgs its
remote ancestors must have been of the insect family. If the thing
follows us, and I think we can be sure that it will, we'll have to take
steps. There is always this advantage--those hounds cannot be controlled
from a flyer, and the beetle-heads never take kindly to foot slogging.
So we won't have to expect any speedy chase. If it slips its masters in
rough country, we can try to ambush it." In the dim light Thorvald was
frowning. "I flew over the territory ahead on two sweeps, and it is a
queer mixture. If we can reach the rough country bordering the sea,
we'll have won the first round. I don't believe that the Throgs will be
in a hurry to track us in there. They'll try two alternatives to chasing
us on foot. One, use their energy beams to rake any suspect valley, and
since there are hundreds of valleys all pretty much alike, that will
take some time. Or they can attempt to shake us out with a dumdum should
they have one here, which I doubt."

Shann tensed. The stories of the effects of the Throg's dumdum weapon
were anything but pretty.

"And to get a dumdum," Thorvald continued as if he were discussing a
purely theoretical matter and not a threat of something worse than
death, "They'll have to bring in one of their major ships. Which they
will hesitate to do with a cruiser near at hand. Our own danger spot now
is the section we should strike soon after dawn tomorrow if the rate of
this current is what I have timed it. There is a band of desert on this
side of the mountains. The river gorge deepens there and the land is
bare. Let them send a ship over and we could be as visible as if we were
sending up flares----"

"How about taking cover now and going on only at night?" suggested
Shann.

"Ordinarily, I'd say yes. But with time pressing us now, no. If we keep
straight on, we could reach the foothills in about forty h