Hal Clement: The Nitrogen Fix

Bones was already halfway to the beach. The others had no chance of catching up with the creature either swimming or running, but in a meter or so of water-too shallow for Bones to swim, too deep for the tentacular legs to work freely-they gained, and were close behind by the time they too had to wade.

The beach was slimy with nitro-life, which was (they hoped) too wet to be a fire hazard, but made running difficult. The larger growths were mostly of the smoldering type as far as they could see, but there was an occasional blaster among them.

As the party reached the base of the little peninsula to the south of their anchorage, with the jail some forty meters ahead and inland, there came a thud which was felt rather than heard. A fountain of red-hot coals rose into view from the other side of the ridge, spread slowly with eye-arresting slowness, and descended again. Some of the glowing fragments landed quite close to the watchers and even closer to the building, and any doubts about the nature of the bushes were quelled as half a dozen of them, struck by the coals, began to smoke and glow. There was no flame, since there was practically no free oxygen to react with the gases being distilled from the plant tissues; the latter burned at all only because of their nitrate content.

The human couple paused and glanced at each other, but Bones kept running toward the jail. After a moment they followed, but both kept glancing quickly to the fire, back to the raft, and forward to the stone structure, while staying as far as possible from any bushes close to their path.

The native had almost reached the building, with the others eight or ten meters behind, when there was a second, heavier explosion. All three stopped to watch the glowing fragments of stems, trunks, and branches fly upward and outward, each trailing a line of red-brown nitrogen dioxide smoke and gas.

They tensed as some of the material passed over their heads, and Earrin and Kahvi held their breaths as several incandescent fragments fell into the water on both sides of the raft.

Kahvi took a step back the way they had come, but stopped as she saw her daughter’s tiny form stand firm between two water buckets. Evidently nothing had hit the tent this time.

Then a scream, in a voice much deeper than Danna’s, turned their attention back toward the jail.

The building had walls of rough stone, with no visible mortar. The cement which held it together as flammable as ordinary tent tissue, but had been applied only to the inside of the walls; it was safe from outside fire unless one of the more flammable varieties of slime were allowed to grow on the stones. The roof, however, was another matter. It had to be transparent to let sunlight reach the oxygen plants inside.

Unless some change had been made since the Fyns’ last visit, it was composed of the same material as their own tent on the raft, and their other bases. It was not actually explosive, but vulnerable to fire whendry.

The scream seemed to suggest that there had been no change, not a surprising situation for the Boston area.

Earrin dashed up to the building; he did not need Bones’ gesture to tell him the cause of the outcry, though only the Observer was tall enough to see all the roof. The man climbed the wall without difficulty, using the ample toe-spaces between the stones. His sponge was already wet.

There were three widening holes in the roof, smoking briskly around their edges. Earrin got as close as he could to the nearest, reached out with his pole, and began sponging its rim. It was tempting to move the pole too fast, but nitrate-fed fires were not smothered; they had to be cooled. Earrin had had far too much experience to let himself be rushed on this job.

This did not seen to be true of the person inside.

There had been no more screams, which was encouraging — perhaps the first had been mere surprise, not panic. Now a sponge was dabbing at the second hole from underneath — but it was going too fast; the widening rim of the opening resumed its hissing and smoking as the sponge passed on.

“Slow down!” Earrin cried as loudly as his mask would allow. “You’re not getting it out!”

A less muffled male voice responded. “But there’s more than one! If I don’t go fast, the others will get too big!”

Earrin was startled by this logic, but attacked from another direction. “We’ll get the others. You stick with that one, and slow down.” His use of the plural had been slightly deceptive, he suddenly realized, since neither Bones nor Kahvi had sponges, but there was no time to make amends for the moral slip. At least it had been effective; the occupant of the jail followed instructions.

Earrin finished the hole he had started, and leaped along the wall to the remaining one. At the same moment another explosion sounded, but he kept his attention on his job. Kahvi and Bones would warn him if any other action was necessary. He wished they had more sponges, but there had been no way of telling before they left the raft just what would be needed; it had been at least as likely that they would have to be hoeing firebreaks around the jail. One thing did occur to him as he moved, and he called out, “Kahvi! Bones! There’s at least one more sponge inside. Check there before you go back to the raft for anything!

“Right,” his wife responded. “That last blast was weaker, and nothing got this far. If I go inside I’ll let you know so you can watch the raft. Danna can handle that much by herself.”

“Right.” Earrin had reached the last hole, and was working on it. It had had time to grow large, over twenty centimeters across, and the sponge might not be enough, but one could only try.

The near edge of the sputtering circle sizzled more loudly as the still-wet tool drank its heat. Earrin moved it along as fast as he dared. The sponge itself was only a dozen centimeters across — it would be nice, he thought fleetingly, if larger ones could be found, but the pseudolife which produced the things had apparently been designed for some long-forgotten purpose that needed small sponges. At least it was still holding plenty of water.

By the time he was halfway around the hole, it was evident that geometry was against him. Without stopping his own efforts, the man called out, “Bones! Knife work!”

The hole was near one corner of the roof, not quite a meter from the south and west walls. The Observer was tall enough to see the situation without climbing, and the tentacles which extended from just below the bulging eyes were more than long enough. One of them slipped the glass-bladed knife from Earrin’s pouch and began sawing at the rim of the hole. The blade was not really knifelike by earlier standards — it would have done better as one half of a pair of scissors — but the tissue gave easily under its attack. Bones started on the side where the fire was already out, slashed outward, and then began to saw clockwise. A strip of separated material began to hang down into the room, and started to flame in the breathable air inside. Bones worked faster, and got the strip separated before it had ignited more of the roof, and the flaming stuff dropped out of sight inside. Earrin held his sponge ready for several seconds, but luck had apparently been with them.

“All right, Kahv,” he finally called. “We got two, the fellow inside put out the other. Can you see if Dan’s all right? This mask window is terrible.”“I can see her pretty well. She’s just standing there, and there’s no smoke, so I guess the raft wasn’t hit. I’ll go back and make sure, and get another sponge; we won’t need a fire break, I’d say. You and Bones stay here — the fire over the hill is still going, judging by the smoke there.”