stared at us in utter horror.
Janus raised his gun again.
"Don't bother," said Allenby tiredly. "I don't think it intends toattack."
"But--"
"I'm sure it isn't a Martian with religious convictions."
Janus wet his lips and looked a little shamefaced. "I guess I'm kind oftaut."
"That's what I _taut_," said Allenby.
The creature darted from behind its rock and, looking at us over itsshoulder, employed six legs to make small but very fast tracks.
We turned our attention again to the desert. Far out, black againstMars' azure horizon, was a line of low hills.
"Shall we go look?" asked Burton, eyes gleaming at the mystery.
Janus hefted his gun nervously. It was still crackling faintly from thedischarge. "I say let's get back to the ship!"
Allenby sighed. "My leg hurts." He studied the hills. "Give me thefield-glasses."
Randolph handed them over. Allenby put them to the shield of his maskand adjusted them.
After a moment he sighed again. "There's a hole. On a plane surfacethat catches the Sun. A lousy damned round little impossible hole."
"Those hills," Burton observed, "must be thousands of feet thick."
* * * * *
The argument lasted all the way back to the ship.
Janus, holding out for his belief that the whole thing was of religiousorigin, kept looking around for Martians as if he expected them to pourscreaming from the hills.
Burton came up with the suggestion that perhaps the holes had been madeby a disintegrator-ray.
"It's possible," Allenby admitted. "This might have been the scene ofsome great battle--"
"With only one such weapon?" I objected.
Allenby swore as he stumbled. "What do you mean?"
"I haven't seen any other lines of holes--only the one. In a battle, thewhole joint should be cut up.
That was good for a few moments' silent thought. Then Allenby said, "Itmight have been brought out by one side as a last resort. Sort of an acein the hole."
I resisted the temptation to mutiny. "But would even one such weapon, inbattle make only _one_ line of holes? Wouldn't it be played in an arcagainst the enemy? You know it would."
"Well--"
"Wouldn't it cut slices out of the landscape, instead of boring holes?And wouldn't it sway or vibrate enough to make the holes miles away fromit something less than perfect circles?"
"It could have been very firmly mounted."
"Hugh, does that sound like a practical weapon to you?"
Two seconds of silence. "On the other hand," he said, "instead of a war,the whole thing might have been designed to frighten some primitiverace--or even some kind of beast--the _hole_ out of here. Ademonstration--"
"Religious," Janus grumbled, still looking around.
We walked on, passing the cactus on the low ridge.
"Interesting," said Gonzales. "The evidence that whatever causes thephenomenon has happened again and again. I'm afraid that the wartheory--"
"Oh, my God!" gasped Burton.
We stared at him.
"The ship," he whispered. "It's right in line with the holes! Ifwhatever made them is still in operation...."
"Run!" yelled Allenby, and we ran like fiends.
* * * * *
We got the ship into the air, out of line with the holes to what wefervently hoped was safety, and then we realized we were admitting ourfear that the mysterious hole-maker might still be lurking around.
Well, the evidence was all for it, as Gonzales had reminded us--thatcactus had been oozing.
We cruised at twenty thousand feet and thought it over.
Janus, whose only training was in photography, said, "Some kind ofomnivorous animal? Or bird? Eats rocks and everything?"
"I will not totally discount the notion of such an animal," Randolphsaid. "But I will resist to the death the suggestion that it forageswith geometric precision."
After a while, Allenby said, "Land, Burton. By that 'canal.' Lots ofplant life--fauna, too. We'll do a little collecting."
Burton set us down feather-light at the very edge of the sprawling flatexpanse of vegetation, commenting that the scene reminded him of hisnative Texas pear-flats.
We wandered in the chilly air, each of us except Burton pursuing hisspecialty. Randolph relentlessly stalked another of the rabbitycreatures. Gonzales was carefully digging up plants and stowing them injars. Janus was busy with his cameras, recording every aspect of Marstransferable to film. Allenby walked around, helping anybody who neededit. An astronomer, he'd done half his work on the way to Mars and woulddo the other half on the return trip. Burton lounged in the Sun, hisback against a ship's fin, and played chess with Allenby, who wascalling out his moves in a bull roar. I grubbed for rocks.
My search took me farther and farther away from the others--all I couldfind around the 'canal' was gravel, and I wanted to chip at some bigstuff. I walked toward a long rise a half-mile or so away, beyond whichrose an enticing array of house-sized boulders.
As I moved out of earshot, I heard Randolph snarl, "Burton, _will_ youstop yelling, 'Kt to B-2 and check?' Every time you open your yap, thiscritter takes off on me."
Then I saw the groove.
* * * * *
It started right where the ground began to rise--a thin, shallow,curve-bottomed groove in the dirt at my feet, about half an inch across,running off straight toward higher ground.
With my eyes glued to it, I walked. The ground slowly rose. The groovedeepened, widened--now it was about three inches across, about one and ahalf deep.
I walked on, holding my breath. Four inches wide. Two inches deep.
The ground rose some more. Four and three-eighths inches wide. I didn'thave to measure it--I _knew_.
Now, as the ground rose, the edges of the groove began to curve inwardover the groove. They touched. No more groove.
The ground had risen, the groove had stayed level and gone underground.
Except that now it wasn't a groove. It was a round tunnel.
A hole.
A few paces farther on, I thumped the ground with my heel where the holeought to be. The dirt crumbled, and there was the little dark tunnel,running straight in both directions.
I walked on, the ground falling away gradually again. The entire processwas repeated in reverse. A hairline appeared in thedirt--widened--became lips that drew slowly apart to reveal the neatstraight four-inch groove--which shrank as slowly to a shallow line ofthe ground--and vanished.
I looked ahead of me. There was one low ridge of ground between me andthe enormous boulders. A neat four-inch semicircle was bitten out of thevery top of the ridge. In the house-sized boulder directly beyond was afour-inch hole.
* * * * *
Allenby winced and called the others when I came back and reported.
"The mystery _deepens_," he told them. He turned to me. "Lead on,Peters. You're temporary _drill_ leader."
Thank God he didn't say _Fall in_.
The holes went straight through the nest of boulders--there'd be a holein one and, ten or twenty feet farther on in the next boulder, anotherhole. And then another, and another--right through the nest in a line.About thirty holes in all.
Burton, standing by the boulder I'd first seen, flashed his flashlightinto the hole. Randolph, clear on the other side of the jumbled nest,eye to hole, saw it.
Straight as a string!
The ground sloped away on the far side of the nest--no holes werevisible in that direction--just miles of desert. So, after we'd staredat the holes for a while and they didn't go away, we headed back for thecanal.
"Is there any possibility," asked Janus, as we walked, "that it could bea natural phenomenon?"
"There are no straight lines in nature," Randolph said, a littleshortly. "That goes for a bunch of circles in a straight line. And forperfe
ct circles, too."
"A planet is a circle," objected Janus.
"An oblate spheroid," Allenby corrected.
"A planet's orbit--"
"An ellipse."
Janus walked a few steps, frowning. Then he said, "I remember readingthat there _is_ something darned near a perfect circle in nature." Hepaused a moment. "Potholes." And he looked at me, as mineralogist, tocorroborate.
"What kind of potholes?" I asked cautiously. "Do you mean where part ofa limestone deposit has dissol--"
"No. I once read that when a glacier passes over a hard rock that'slying on some softer rock, it grinds the hard rock down into the softer,and both of them sort of wear