g minutes, trying to figure out the reason for the
phenomenon, then he almost leaped out of his skin. The water was
reflecting the yellow light! It didn't come from the water the way the
luminous silver did!

He got to his feet. Reflection meant man-made light!

It was hard to follow the faint yellow light. When he switched on the
infrared, the light vanished completely. When the infrared was off, he
couldn't find his way.

He compromised, going a hundred feet or so with the infrared on, then
turning it off and sitting quietly until his eyes adjusted themselves
and he could see the yellow glow once more. After he did this a few
times he could see that the light was growing slightly stronger.

Then, as he progressed, he realized why he couldn't see the source of
the light. It was around a corner of the rock wall.

After several minutes of alternate walking and waiting he reached the
corner. It dropped sharply into the water, and when he flashed the
infrared down, he saw that the water was black. No shelf here to walk
on. He debated for a moment. He could swim around, or he could try to
find another way. There were plenty of cave openings. One of them might
go through.

He had been lost once, and he didn't intend to let that happen again. He
tore open the packet of emergency rations he had brought, searching for
something with which to lay a trail.

Inside the waxed container were little cans of food and a packet of hard
crackers. The crackers would do.

But looking at the food reminded him that he hadn't eaten in a long
time. He didn't know if it was hours, or days. He had lost all track of
time. He took the can key and unwound the narrow sealing strip on a
container of cheese. It tasted wonderful. He devoured every bit of it,
including the crumbs left in the can. Then he opened a can of meat and
ate that, too. He had been sipping at his canteen at various times, but
it was still more than half full. He detached the canteen cup and filled
it from the lake, tasting it cautiously. The water had a flat taste,
like boiled water, but it was all right. He drank deeply, then filled
the canteen.

His hunger and thirst satisfied, he surveyed the various openings around
him, then chose the one nearest the corner he wished to get around. At
the very entrance, he placed the empty cheese tin. Inside the cave, he
turned to be sure it was clearly visible, then walked across to an
opening that seemed likely to lead him in the