"And for the theft of the sugar," Joss put in. "Though heaven only knows why they should want to steal that."

"Sugar!" I exclaimed, and then the question died in my throat. I happened to be looking straight at the little Jew, Theodore Mahler, and the nervous start he gave, the quick flicker of his eyes in Joss's direction, was unmistakable. I knew I couldn't have imagined it. But I looked away quickly, before he could see my face.

"Our last bag," Joss explained. "Maybe thirty pounds. It's gone. I found what little was left of it – just a handful lying on the floor of the tunnel – mixed up with the smashed valves."

I shook my head and said nothing. The reason for this last theft I couldn't even begin to imagine.

Supper that night was a sketchy affair – soup, coffee and a couple of biscuits each as the only solids. The soup was thin, the biscuits no more than a bite and the coffee, for me at any rate, all but undrinkable without sugar.

And the meal was as silent as it was miserable, conversation being limited to what was absolutely necessary. Time and again I would see someone turn to his neighbour and make to say something, then his lips would clamp tightly shut, the expression drain out of his face as he turned away without a word: with almost everyone thinking that his or her neighbour might be a murderer, or, what was almost as bad, that his or her neighbour might be thinking that he was a murderer, the meal was by all odds the most awkward and uncomfortable that I'd ever had. Or, that is, the first part of it was: but by and by I came to the conclusion that I'd a great deal more to worry about than the niceties of social intercourse.

After the meal I rose, pulled on parka and gloves, picked up the searchlight; told Jackstraw and Joss to come with me and headed for the trap-door. Zagero's voice stopped me.

"Where you goin', Doc?"

"That's no concern of yours. Well, Mrs Dansby-Gregg?"

"Shouldn't you – shouldn't you take the rifle with you?"

"Don't worry." I smiled thinly. "With everyone watching everyone else like hawks, that rifle's as safe as houses."

"But – but someone could jump for it," she said nervously. "They could get you when you're coming down the hatch – "

"Mr Nielsen and I are the last two persons they'd ever shoot. Without us, they couldn't get a mile from here. The most likely candidates for the next bullet are some of yourselves. You're absolutely inessential and, as far as the killers are concerned, represent nothing more than a waste of priceless rations." With this comforting thought I left them, each person trying to watch all the others at one and the same time, while doing his level best to give the appearance of watching no one.

The wind was so slight now that the anemometer cups had stopped turning. The dying embers of the burnt-out plane were a dull smouldering glow to the north-east. The snow had gone completely and the first faint stars were beginning to show through the thinning cloud above. It was typically Greenland, this swift change in the weather, and so, too, was the temperature inversion that would surely follow in the morning, or before morning. Twelve hours from now it was going to be very cold indeed.

With searchlight and torches we examined every inch of the tractor and sledges, above and below, and if there had been a pin there I would have sworn that we couldn't have missed it, far less anything so large as a couple of guns. We found nothing.

I straightened, and turned to look at the glow that was lightening the sky to the east, and even as I stood there with Joss and Jackstraw by my side the moon, preternaturally large and rather more than half full, heaved itself above the distant horizon and flooded the ice-cap with its pale and ghostly light, laying down between itself and our feet a bar-straight path of glittering silver grey. We watched in silence for a full minute, then Jackstraw stirred. Even before he spoke, I knew what was in his mind.

"Uplavnik," he murmured. "Tomorrow, we set off for Uplav-nik. But first, you said, a good night's sleep."

"I know," I said. "A traveller's moon."

"A traveller's moon," he echoed.

He was right, of course. Travel in the Arctic, in winter, was regulated not by daylight but my moonlight. And tonight we had that moon – and we had a clear sky, a dying wind and no snow at all. I turned to Joss.

"You'll be all right alone?"

"I have no worries," he said soberly. "Look, sir, can't I come too?"

"Stay here and stay healthy," I advised. "Thanks, Joss, but you know someone must remain behind. I'll call you up on the usual schedules. You might get a kick out of the RCA yet. Miracles still happen."

"Not this time, they won't." He turned away abruptly and went below. Jackstraw moved across to the tractor – we didn't say another word to each other, we didn't have to – and I followed Joss down to the cabin. No one had moved an inch, as far as I could see, but they all looked up as I came in.

"All right," I said abruptly. "Get your stuff together and pile on every last stitch of clothes you can. We're leaving now."

We left, in fact, just over an hour later. The Citroen had been lying unused for the better pan of a fortnight, and we had the devil's own job getting it to start. But start it eventually did, with a roar and a thunderous clatter that had everybody jumping in startlement then looking at it in dismay. I knew the thoughts in their minds, that they'd have to live with this cacophony, this bedlam of sound assaulting their shrinking eardrums for no one knew how many days to come, but I wasted little sympathy on them: at least they would have the protection of the wooden body while I would be sitting practically on top of the engine.

We said our goodbyes to Joss. He shook hands with Jackstraw and myself, with Margaret Ross and Marie LeGarde, and, pointedly, with no one else. We left him standing there by the hatchway, a lonely figure outlined against the pale light of the steadily climbing moon, and headed west by south for Uplavnik, three hundred long and frozen miles away. I wondered, as I knew Joss was wondering, whether we would ever see each other again.

I wondered, too, what right I had in exposing Jackstraw to the dangers which must lie ahead. He was sitting beside me as I drove, but as I looked at him covertly in the moonlight, at that strong lean face that, but for the rather broad cheekbones, might have been that of any Scandinavian sea-rover, I knew I was wasting my time wondering. Although nominally under my command, he had only been lent me, as other Greenlanders had been lent as an act of courtesy by the Danish Government to several IGY stations, as a scientific officer – he had a geology degree from the University of Copenhagen and had forgotten more about the ice-cap than I would ever know – and in times of emergency, especially where his own pride, and he had plenty of that, was concerned would be extremely liable to do what he thought best, regardless of what I thought or said. I knew he wouldn't have remained behind even if I had ordered him to– and, if I were honest with myself, I was only too damned glad to have him along, as a friend, as an ally, and as insurance policy against the disaster that can so easily overtake the careless or the inexperienced on the ice-cap. But even so, even though I quieted my conscience as best I could, it was difficult to push from my mind the picture of his dark vivacious young schoolteacher wife and little daughter, the red and white brick house in which I'd lived for two weeks as a guest in the summer. What Jackstraw thought was impossible to say. He sat immobile as if carved from stone, only his eyes alive, constantly moving, constantly shifting, as he probed for sudden dips in the ice-cap, for differences in the structure of the snow, for anything that might spell trouble. It was purely automatic, purely instinctive: the crevasse country lay, as yet, two hundred and fifty miles away, where the ice-cap started to slope sharply to the sea, and Jackstraw himself maintained that Balto, his big lead dog, had a surer instinct for crevasses than any human alive.