“Anything changing, Captain?” Kervenser’s jocular attitude vanished at the possibility of action.

“Possibly. Stars are showing above, but not to the south. Not anywhere near the horizon, in fact. Try a spot.”

The first officer obeyed, and a spear of light flicked upward from a point behind the bridge as he touched one of the few electrical controls. Dondragmer manipulated a pair of pull cables, and the beam swung toward the western horizon. A wail, the rough equivalent of a human grunt of surprise, came from Kervenser as the descending beam became more visible parallel to the ground.

“Fog!” exclaimed the helmsman. “Thin, but that’s what’s blocking the horizon.” Dondragmer gave a gesture of agreement as he reared to a speaking tube.

“Research!” he hooted. “Possible precipitation. Check what it is, and what it could do to this water-ice under us.”

“It will take a while to get a sample, sir,” came the answer. “We’ll be as quick as we can. Are we cleared outside, or will we have to work through the hull?”

The captain paused for a moment, listening to the wind and remembering how it had felt.

“You’re cleared out. Be as quick as you can.

“On the way, Captain.”

At Dondragmer’s gesture, the first officer cut off the spot, and the three went to the starboard end of the bridge to watch the outside party.

They moved quickly but the haze was becoming more noticeable by the time the lock opened. Two caterpillar-like forms emerged carrying a cylindrical package between them. They made their way forward to a point almost under the watchers, and set up their equipment — essentially a funnel facing into the wind and feeding into a filter. It took several minutes to convince them that they had a big enough sample, but eventually they dismantled the equipment, sealed the filter into a container to preserve it from the lock fluid and made their way back to the entrance.

“I suppose it will take them a day to decide what it is, now,” grumbled Kervenser.

“I doubt it,” replied the captain. “They’ve been playing with quick tests for water-ammonia solutions. I think Borndender said something about density being enough, given a decent-sized sample.”

“In that case, why are they taking so long?”

“They could hardly be out of their air suits yet,” the captain pointed out patiently.

“Why should they get out of them before making delivery to the lab? Why couldn’t—”

A hoot from a speaking tube interrupted him. Dondragmer acknowledged.

“Just about pure ammonia, sir. I think it was super-cooled liquid droplets; it froze into a froth in the filter, and let quite a bit of outside air loose when it melted in here. If you should smell oxygen for the next few minutes, that’s it. It may start icing up the hull, and if it coats the bridge, as it did the filter, it will interfere with your seeing, but that’s all I can guess at right now in the way of trouble.”

It was not all Dondragmer could imagine, but he acknowledged the information without further comment.

“This sort of thing hasn’t happened since we’ve been here,” he remarked. “I wonder whether it’s some sort of seasonal change coming on. We are getting closer to this body’s sun. I wish the human crowd had watched this world for a longer time before they sold us on the idea of exploring it for them. It would be so nice to know what comes next. Kervenser, start engines. When ready, turn bow into wind and proceed ahead dead slow, if you can still see out. If not, circle as sharply as possible to port, to stay on surface we know. Keep an eye on the treads — figuratively, of course; we can’t see them without going out — and let me know if there’s evidence that anything is sticking to them. Post a man at the stern port; our trail might show something. Understand?”

“The orders, yes, sir. What you’re expecting, no.”

“I may be wrong, and if I’m right there’s probably nothing to do anyway. I don’t like the idea of going outside to clear the treads manually. Just hope.”

“Yes, sir.” Kervenser turned to his task, and as the fusion engines in the Kwembly’s trucks came to life, the captain turned to a block of plastic about four inches high and wide and a foot long, which lay beside his station. He inserted one of his nippers in a small hole in the side of the block, manipulated a control, and began to talk.

His voice traveled fast, but it was a long time on the way. The radio waves carrying it sped through Dhrawn’s heavy but quickly thinning atmosphere and through the space beyond for second after second. They weakened as they traveled, but half a minute after they had been radiated their energy was still concentrated enough to affect a ten-foot dish antenna. The one they encountered was projecting from a cylinder some three hundred feet in diameter and half as long: it formed one end of a structure resembling a barbell, spinning slowly about an axis perpendicular to its bar and midway between its weights.

The current induced by the waves in the antenna flicked, in a much shorter time, into a pinhead-size crystal which rectified it, enveloped it, used the envelope to modulate an electron stream provided by a finger-sized generator beside it and thus manipulated an amazingly old-fashioned dynamic cone in a thirty-foot-square room near the center of the cylinder. Just thirty-two seconds after Dondragmer uttered his words they were reproduced for the ears of three of the fifteen human beings seated in the room. He did not know who would be there at the time, and therefore spoke the human tongue he had learned rather than his own language; so all three understood him.

“This is an interim report from the Kwembly. We stopped two and a half hours ago for routine maintenance and investigation. Wind was about 200 cables at the time, from the west, sky partly cloudy. Shortly after we got to work the wind picked up to over 3,000 cables—”

One of the human listeners was wearing a puzzled expression, and after a moment managed to catch the eye of another.

“A Mesklinite cable is about 206 feet, Boyd,” the latter said softly. “The wind jumped from about five miles an hour to over sixty.”

“Thanks, Easy.” Their attention returned to the speaker.

“Fog has now closed us in completely, and is getting ever thicker. I don’t dare move as I had planned; just in circles to keep the treads from icing. The fog is super-cooled ammonia according to my scientists, and the local surface is water snow. It doesn’t seem to have occurred to my research people, but with the temperature in the seventies it seems to me there’s a chance of the fog’s dissolving some of the water-ice to make a liquid. I realize this machine is supposed to float, and I don’t suppose the surface would melt very deeply anyway, but I’m wondering whether anyone has thought much about what will happen if a liquid freezes around our treads. I have to admit I never have, but the thought of chipping the ship loose by muscle power isn’t inviting. I know there’s no special equipment on board to handle such a situation, because I assembled and loaded this machine myself. I’m simply calling to report that we might possibly be here a good deal longer than planned. I’ll keep you informed, and if we do get immobilized we’ll be glad of projects to keep our scientists busy. They’ve already done most of the things you set up for an ordinary stop.

“Thanks, Don,” replied Easy. “We’ll stand by. I’ll ask our observers and aerologists whether they can make a guess about the size of your fog bank, and how long it’s likely to stay around you. They may have some useful material already, since you’ve been on the night side for a day or so. For that matter, they may even have current pictures; I don’t know all the limits of their instruments. Anyway, I’ll check and let you know.”