“Can I have the knife today?” Angelina asked. “So I can break trail.”

“Gone,” I said, pointing to a damp knife—shaped spot in the sand.

“I’ll see if I can find a rock that will do.”

She found one shaped not unlike a hand ax, traditional tool of mankind. I looked for another one, then put a few more rocks in my pockets. Angelina led the way since she was as strong and fit as I was, possibly with better reflexes. And I was not about to start discussing the equality of the sexes with her at any time.

With our stomachs full, our bodies rested, we made good time. And followed the path around the clearing. I stopped just long enough to throw a rock at the creature there; I had carried it all the way from the beach just for this moment. It thudded nicely and the tentacle thrashed violently.

“I wish… I had a power saw the thing said.

“Did you think that?” I asked.

“You better believe it.”

We struggled up the last and steepest part of the path to the ridge at the top. And stopped.

“Quite a change,” Angelina said.

All the green growth ended sharply. As though a line had been drawn along the summit. A bowl in the hills stretched out ahead of us. Completely devoid of life. Sand and rock and nothing more; an empty, barren desert.

“You said that it never rains on this planet?” I asked.

“Never.”

“If it did that would also be a sloppy end for the glass life forms. It also means that the carbon and chlorophyll life can’t get too far from the ocean. I’ll bet they dip their roots into it or get dew from the air. So up here—no water, so no life.”

“But the path goes on,” she said, pointing.

“Interesting. So I guess that we do too.”

We followed it as it twisted and turned between boulders as big as houses, on to a central flat desert of sand.

“What on earth is that?” Angelina asked. I could not think of an answer.

In the sand was a small pyramid apparently made of rock. It was seamless—but hollow. That was obvious because the top was broken off and we could see inside. It was empty. But what was most interesting was the slightly larger pyramid close by. Also with an opening in the top. And the next and the next. Stretching out in a straight line across the desert. Each one with an opening in the top, each larger than the one before.

“An alien enigma,” I said brightly; Angelina just sniffed, not considering this worth an answer. We left the path and walked along the line of pyramids. There were over thirty of them, the final one taller than we were.

“The last one,” Angelina said, pointing. “The top. It comes to a point—and it is solid. Any explanations?”

For a rare moment I was silent.

“Shall I tell you what is happening?” she said.

“Speak, I beg of you.”

“This has obviously been constructed by a silicon life form. It digests sand and excretes rock thus building a pyramid around itself. When it grows too big for the pyramid it cracks out, moves along and builds another one.”

“Highly interesting,” I said, dazed by her logic. “But how did it get to build the first one in the first place—and how does it build a pyramid from the inside?”

“You can’t expect me to know everything,” she said, with impeccable logic. “Let’s get back to the path.”

“Let’s not quite yet,” I said pointing. “Isn’t that something following the path and moving towards us?”

“Some things not a thing.”

“You’re right. Any reason we shouldn’t stay out of sight until we see what they are?”

She nodded and we stepped into the shadow of the largest pyramid where we might see and possibly not be seen. Angelina cocked her head, then pressed her ear to the side of the pyramid. “Listen,” she said. “Isn’t there a kind of crunching sound coming from inside?”

“Please, not now. Possibly later. One alien mystery at a time if you don’t mind.”

The marching file of creatures was surely mystery enough. There were eleven of them and they were roughly man—size. But the resemblance ended right there. A fringe of legs or tentacles or something twitched quickly against the ground and carried each creature along. These moving parts supported a solid trunk the color and texture of tree bark—it could be a tree trunk for all we knew. A single stalk, very much like the one on the creature that had tried to eat me, emerged from the top of the trunk with what looked like a bulbous eye at the end. The eyes bobbed and looked about, apparently not seeing us pyramid lurking in the shadow.

They shuffled by in silence, stirring up a quickly settling cloud of dust, climbed over the rim and vanished down the ridge on the other side.

“Now will you listen to the pyramid?” Angelina asked.

“Yes, of course, sure.” I listened and perhaps I did hear a distant crunching. “I can hear something…”

“They’re coming back,” she said.

And so they were. Whether it was the same bunch or a different lot it was of course impossible to tell. Different ones, surely, because in the brief time they had been out of sight they had changed completely. The ribbed trunks had become globeshaped and transparent, expanded from within so the ribbing now formed irregular stripes on the surface.

“They’re filled with water,” Angelina said, and I nodded dumb agreement.

“Possibly, possibly,’ I muttered.

“They march out of the desert and fill with water from a spring or from the ocean. Then march back with it. Why?”

“There is only way to find out—follow them.”

Perhaps it was not wise. Possibly dangerous. But there were too many curious and unsolvable puzzles on this planet. We both had the desire to see if we might possibly solve at least one of these. When they were out of sight we followed them down the path.

Nor did we have far to go. The path led to a row of large boulders and vanished between two of them.

“Suspicious,” I said. “Those rocks have been placed there.”

~’It could be a natural formation.”

“It could, but the problem is the same. Do we stay out—or go in to investigate. And you will recall what happened the last time I got nosy..

“Behind you!”

I took one look and jumped aside. Another string of water carriers was approaching—and they were almost upon us. We stood by the path tense and ready to fight.

And while they were aware of us, our presence was completely ignored. The string shuffled on by in silence, each eye focusing on us in turn as they passed.

“They don’t seem too interested in us,” I said.

“Well I’m interested in them. Let’s go.”

We did. Slipping between the large boulders, then following the path between a second row to walk inside a circular, rock—girt area. Where we stopped—and did our best not to gape and bulge our eyes as though we had a joint IQ about that of body temperature.

It was so alien that it was hard to make out just what was happening here. One thing at least was certain—we knew where the water was going. The creatures we had been following wandered through a green labyrinth spraying water and shrinking their bodies at the same time. When this was finished, one walked away from the growth, then another and another. They milled about in a little group until, with sudden decision—or obeying some unseen signal—a line formed and they shuffled through the exit and were gone.

We walked closer to the confused growth, stopped when we saw movement under the broad, leaflike structures. In the semidarkness, spiderlike creatures were climbing about, apparently tending the growth. Fragments of green fell down to the ground where other creatures cleaned them up. Another dropped down on the end of a cord or tentacle clutching something red.

“Very much like that fruit you got your neck squeezed for,” Angelina said.

“Could be, could be—and look where it’s going.”

A tall opening in the rock led to some kind of cavern beyond. I bent to try and look inside when there was a light pulling at my leg, a feathery touch.