Hal Clement - The Nitrogen Fix

Several minutes of waiting made it reasonably sure that no people had seen. Slowly, carefully, and as silently as the great body could manage, Bones worked inland through the sometimes slippery and sometimes spiky plants. The way led uphill toward the top of the same ridge which had concealed the fire earlier in the day, but for a long time no signs of burning could be found. The Observer worked back and forth — north and south — rather than straight eastward and upward, but for a long time had no luck. This was strange; it was hard to believe that the blaze had not covered a large area. It was almost completely dark by now, with neither the moon nor the comet in the sky, but Bones’ huge eyes were far more efficient than those Of any human being.

There were no informative sounds, either. The whips, leaves, branches and spines of the various plants and plantlike pseudos were moving in the light breeze to create a background murmur, but there were no large animals other than human beings and Observers now on Earth. Bones could be reasonably sure that none of these was moving anywhere close by. Perhaps the fire had been of natural origin after all — still, those people whose appearance had caused Bones to leave Earrin alone had been coming from somewhere on this side of the peninsula. Care was still in order; would all of any group have gone over to the jail?

Maybe, but maybe wasn’t safe enough.

Then the risk dropped from consideration as a faint suggestion of radiant heat manifested itself.

Bones turned slowly until both lateral fins received the sensation equally, and for several seconds both great eyes bored without result in the indicated direction, northward. Then, carefully, the Observer moved the same way. At first the surrounding plants interfered with clear vision, but then the higher growth began to thin out ahead. After two hundred meters or so there was even a horizon; stars could be seen nearly down to the ridge at the right, and almost as low directly ahead. In the latter direction the points of light were trembling and quivering more than usual. A heat source must lie that way.

Fifty meters further along, eyesight confirmed the deduction. Ahead lay a long pile of stones across the researcher’s line of travel, a roughly made wall half the height of a man. For the last ten meters before reaching it there was no vegetation at all, and the ground felt very warm. The wall, or what had been a wall, surrounded a space some fifteen meters across; inside this area lay a bed of still glowing coals.

The whole thing had to be man-made, but what did people want with such a huge fire? What could they learn from it? Or, since it was now pretty clear that human beings had other drives than the hunger for knowledge, what appetite could it satisfy? Certainly not the urge for nourishment which drove the Fyns so relentlessly. What would Earrin, or Kahvi, or Danna get from such an operation? Bones was as willing to speculate as any human being, but much less willing than most of that species to be satisfied with the results of speculation. The hunger for knowledge which characterized the Observer species could no more be satisfied with “ maybes” and daydreams than a starving human being could becontented by chewing on a twig. More observed facts would have to accumulate. Bones happilv set about finding them.

The stone was typical human tumbled-rock work, except for the lack of any mortar or cement. That might be due to the heat — but hold back on inferences! The rocks themselves were typical of the area, and showed no signs of artifical shaping.

Bones was a couple of thousand years too late to have seen a New England stone wall — the wild erosion which had accompanied the atmosphere change had removed all such loose structures — and could not read any archaeological implications into the fragments. The Observer was now sure that the units had reached Earth much sooner after its atmosphere change than they had ever managed before.

Certainly it was the first time they had found large, active animal life which seemed to have survived from the free-oxygen era; but ideas about possible connections between that life and the change itself were still very hypothetical, and a science of archaeology was still to develop.

The stones were still unpleasantly hot, but Bones used touch as well as sight to gather data. There was dried, crumbling dirt on and between some of the boulders, but no obvious way to tell whether this had been intended to fill spaces, or simply too much of a nuisance to clean off when the rocks had been moved originally. Bones was inclined to suspect the latter, partly because the dirt did not occur everywhere and partly because of the prejudice against unnecessary labor which Earrin and Kahvi showed so strongly. The presumption that this was a standard human characteristic was risky but not unreasonable.

Whatever the structure and fire had been intended for, the purpose seemed to have been fulfilled; there were no people around now. The fire itself had completed its violent stage only recently — this would have been obvious even if Bones had not been watching at the time. Coals from a fire did not last very long with no oxygen to diffuse into the bed, and the Observer had seen plenty of fires since coming to Earth. People who wanted something from the blaze would presumably have waited around to get it, rather than travelling away and back again — this, again, was an inference from the Fyn family behavior, but seemed reasonable.

Having reached this tentative opinion, Bones relaxed some of the precautions to avoid observation and moved more freely around the edges of the big fireplace. This proved to be a mistake, like the inference itself.

Human voices, Bones could not tell how many, suddenly sounded from the west, toward the shore where the researcher had landed. They were not nearly as far away as the shore, but not so close as to remove all hope that the Observer had escaped their sight. The fish-body dropped to horizontal and moved as quickly as all six tentacles — the four normally used for walking and the two handling ones — could carry a hundred and twenty kilograms along the remains of the wall. This speed was normally faster than a human being could run for more than a few seconds, slender as the tentacles were.

The internal engineering and biochemistry of the body were very different from those of Earth’s former oxygen-using endoskeletal organisms. This time, however, the speed was not great enough.

Bones rose briefly to see how close the people were, and a chorus of yells rose suddenly, clearly a view-halloa, even though the Words were not distinguishable. Bones dropped back to all sixes, but the crashing of bushes showed that the human beings had also put on speed. The Observer was no longer visible against the sky, which had brightened in the east with the approach of moonrise, but the people had seen enough.

Bones, originally between them and the fireplace, got around a corner of the latter and headed toward the east at top speed. Breaking realwood indicated that the pursuers were spreading out on each side to forestall any dodging; it looked for a moment as though Bones would be able to keep ahead of them over the hilltop and down to the water on the raft side, which would be enough.

Certainly they could not pursue through water — human beings simply weren’t built for fast swimming.

However, Bones didn’t even reach the top of the ridge. Fifty meters or more short of that goal, the ground suddenly became impassable. Wherever a tentacle touched it, unbearable pain caused the limb to draw back out of control. The Observer could not see what was responsible, but in a matter of seconds found it impossible to travel in any direction. The mysterious agent that caused the agony had transferreditself to the tentacles. No matter what they touched now, the pain resulted.