hunderstorms that sometimes sweep Rio.

Then the clear road to the flying field. Rio has the largest
metropolitan district in the world, but a great deal of it is piled on
end, and Rio itself built on most of the rest. The flying field is
necessarily some miles from even the residential districts, for the
sake of a level plain of sufficient area.

The car shot ahead through practically untouched jungle, interspersed
with tiny clearings in which were patchwork houses that might have
been a thousand miles in the interior instead of so near the center of
all civilization in Brazil. Up smooth gradients. Around beautifully
engineered curves.

* * * * *

Bell put aside one revolver long enough to search Ribiera carefully.
He found a pearl-handled automatic, and handed it to Paula.

"Worth having," he said cheerfully. "I wonder if you'd mind searching
the chauffeur: with that gun at his head I think he'd be peaceful. You
needn't have him stop."

Paula stood up, smiling a little.

"I did not think I lacked courage, Senhor," she observed, "but you
have taught me more."

"_Nil desperandum_," said Bell lightly. He relaxed deliberately.
Matters would be tense at the flying field, and he would need to be
wholly calm. There was little danger of an attempt at rescue here, and
the necessity of being ready to shoot Ribiera at any instant was no
longer a matter of split seconds.

He watched, while, bent over the back of the front seat, she extracted
two squat weapons from the chauffeur's pockets.

"Quite an arsenal," said Bell as he pocketed them. He turned
pleasantly to Ribiera. "Now, Ribiera, you understand just what I want.
That big amphibian plane of yours is fairly fast, and once when I was
merely your guest you assured me that it was always kept fueled and
even provisioned for a long flight. When we reach the flying field I
want it rolled out and warmed up, over at the other end of the field
from the flying line. We'll go over to it in the car.

"And I've thought of something. It worried me, before, because
sometimes if a man's shot he merely relaxes all over. So while we're
at the flying field I'm going to be holding back the triggers of these
guns with my thumbs. I don't have to pull the trigger at all--just let
go and they'll go off. It isn't so fine an adjustment as I had just
now, but it's safer for you as long as you behave. And you might urge
your chauffeur to be cautious. I do ho