“Borndender?” queried someone. Barlennan gestured affirmatively and went on.

“The snow field started here.” He crawled to a spot nearly four feet northwest of the position marker. “It lies between a couple of mountain ridges, which we have indicated only roughly. Destigmet’s balloons haven’t gotten this far south yet, or at least word hasn’t reached us and Don’s fliers haven’t seen much. Just now, while the Kwembly was stopped for a routine maintenance check, a heavy wind came up, and then a dense fog of pure or nearly pure ammonia. Then, quite suddenly, the temperature rose several degrees and they found themselves afloat, being blown roughly eastward by the wind. We would like explanations and we badly need constructive advice. Why did the temperature go up, and why did the snow melt? Is there any connection between the two? Remember that the highest temperature they mentioned was only about a hundred and three, twenty-six or -seven degrees below the melting point of water. Why the wind? How long is it likely to last? It’s carrying the Kwembly toward the hot regions inside Low Alpha south of the Esket site.” He gestured toward a heavily red-marked section of the floor. “Can we tell how far they’ll be carried? I didn’t want Dondragmer to go out on this trip, and I certainly don’t want to lose him even if we don’t agree completely.

“We’ll call for what help we can get from the men, but you’ll have to use your brains, too. I know some of you have been trying to make sense out of Dhrawn’s climatology; do you have any worthwhile ideas which might apply here?”

Several minutes of silence followed. Even those in the group most given to uttering rhetorical speeches had been working with Barlennan too long to risk them now. For some time no really constructive ideas came up. Then one of the scientists scuttled toward the door and vanished, with “Just a moment, I have to check a table” floating behind him. He was back within thirty seconds.

“I can account for the temperature and melting,” he said firmly. “The ground surface was water ice, the fog ammonia. The heat of solution as they met and mixed would have caused the temperature rise. Ammonia-water solutions form eutectics which can melt as low as seventy-one.

Mild hoots of appreciation and approving gestures of nipper-equipped arms greeted this suggestion. Barlennan went with the crowd, though words had been used which were not entirely familiar to him. But he was not through with his questions.

“Does that give us any idea how far the Kwembly will be carried?”

“Not in itself We need information about the extent of the original snow field,” was the answer. “Since only the Kwembly has been in the area, about the only hope is the photo maps made by the humans. You know how little we can get from those. Half the time you can’t differentiate between ice and clouds. Besides they were all made before we landed here.”

• “Give it a try, anyway,” ordered Barlennan. “With luck, you can at least tell whether those mountain ranges to the east are blocking the Kwembly’s present path. If they are, it’s hard to see how the craft could be carried more than a few hundred thousand cables.”

“Right,” answered one of the investigators. “We’ll check. Ben, Dees, come along; you’re more used to the photos than I am.” The three vanished through the door. The others broke up into small groups, muttering arguments to each other and waving excitedly, now at the map underfoot, now at items presumably in the nearby laboratories. Barlennan endured this for several minutes before deciding that a little more guidance was needed.

“If that plateau Don was crossing was such pure water, there couldn’t have been any ammonia precipitation there for a long, long time. Why should things have changed so suddenly?”

“It almost has to be a seasonal effect,” answered one of the men. “I can only guess, but I’d say it had something to do with some consistent change in the wind pattern. Air currents from different parts of the planet will be saturated with water or ammonia according to the nature of the surface they pass over, mostly its temperature, I suppose. The planet is nearly twice as far from its sun at one time as at another and its axis is much more inclined than Mesklin’s. It’s easy to believe that at one time of year only water is precipitated on that plateau and at another it gets supplied with ammonia. Actually, the vapor pressure of water is so low that it’s hard to see what situation would get water into the atmosphere without supplying even more ammonia, but I’m sure it’s possible. We’ll work on it, but it’s another of those times when we’d be a lot better off with world-wide, year-round information. These human beings seem to be in an awful hurry; they could have waited a few more years to land us here, I should think.”

Barlennan made the gesture whose human equivalent would have been a noncommittal grunt. “The field data would be convenient. Just think of yourself as being here to get it instead of having it given to you.

“Of course. Are you going to send the Kalliff or the Hoorsh out to help Dondragmer? This is certainly different from the Esket situation.”

“From our point of view, yes. It might look funny to the humans, though, if I insisted on sending out a rescue cruiser this time after letting them talk me out of it before. I’ll think it over. There’s more than one way of sailing upwind. You do that theoretical work you’ve just been talking about, but be thinking about what you’d want to take on a field trip up toward the Kwembly.”

“Right, Commander.” The scientist started to turn away, but Barlennan added a few more words.

“And Jemblakee. No doubt you’ll be strolling over to Communications to talk to your human colleagues. Please don’t mention this, what was it, heat of solution and eutectic business. Let them mention it first, if they’re going to, and be properly impressed when and if they do. You understand?”

“Perfectly.” The scientist would have shared a grin of understanding with his commander if their faces had been capable of that sort of distortion. Jemblakee left, and after a moment’s thought Barlennan did the same. The remaining researchers and technicians might possibly be the better for his presence to keep their centerboards down but he had other things to do. If they couldn’t hold course without his pincers on their helms, they’d just have to drift for a while.

He should talk to the human station soon; but if there was going to be an argument, as seemed rather likely, he had better do a little course-plotting himself Some of the two-legged giants, Aucoin, for example, who seemed to have a great deal to say about their policy, were reluctant to expend or even risk any sort of reserve equipment, no matter how important the action seemed from the Mesklinite viewpoint. Since the aliens had paid for it, this was perfectly understandable, even laudable. Still there was nothing immoral about talking them around to a more convenient attitude if it could be done. If he could arrange it, the best plan would be to work through that particularly sympathetic female named Hoffman. It was too bad the human beings kept such irregular hours; if they had set up decent, regular watches in their communication section Barlennan would long since have worked out their schedule and been able to pick his party. He wondered, not for the first time, whether the irregular schedule might not be deliberately set up to block that very action, but there seemed no way to find out. He could hardly ask.

The Settlement’s comm center was far enough from the laboratories to give him thinking time en route. It was also close enough to his office to encourage a pause for making a few notes before actually opening the verbal fencing match.

The central theme would have to be the question of rescue, if Dondragmer’s trouble wound up crippling his cruiser. If the previous situation involving the Esket months before were any indication, the tightwads up above would be basically against sending the Kalliff Of course, there was nothing they could do if Barlennan chose to go his own way in that matter, or in any other, but the commander was hoping to keep that fact cushioned in the decencies of polite conversation. He would be happiest if that aspect of the situation never came up at all. This was one reason he hoped to work Easy Hoffman into the other end of the discussion. For some reason, she seemed prone to take the Mesklinite side when disagreements arose. She was certainly one reason that there had been no open argument during the Esket incident, though a more important reason was that Barlennan had never had the slightest intention of sending a rescue cruiser before and had therefore actually been siding with Aucoin.