As the wind rose, the undulations grew more marked. And when Jupiter came up, its yellow light brought out every jag and crag of the rocky ground, toward every one of which, in turn, the sleigh seemed headed. And by the time the giant planet had shoved completely over the horizon, the curse of drink - which departs from the Ganymedan organism just as quickly as it descends - began removing itself from the spinies.

The hindmost spinie came out of it first, tasted the inside of his mouth, winced and swore off drink. Having made that resolution, he took in his immediate surroundings languidly. They made no immediate impression on him. Only gradually was the fact forced upon him that his footing, whatever it was, was not the usual stable one of solid Ganymede. It swayed and shifted, which seemed very unusual.

Yet he might have attributed this unsteadiness to his recent orgy, had he not been so careless as to drop his glance over the railing to which he was anchored. No spinie ever died of heart-failure, as far as is recorded, but, looking downward, this one almost did.

His agonized screech of horror and despair brought the other spinies into full, if headachy, consciousness. For a while there was a confused blur of squawking conversation as the animals tried to get the pain out of their heads and the facts in. Both aims were achieved and a stampede was organized. It wasn't much of a stampede, because the spinies were anchored tightly. But, except for the fact that they got nowhere, they went through all the motions of a full gallop. And the sleigh went crazy.

Olaf grabbed his beard a second before it let go of his ears.

'Hey!' he shouted.

It was something like saying 'Tut, tut' to a hurricane.,

The sleigh kicked, bucked and did a hysterical tango. It made sudden spurts, as if inspired to dash its wooden brains out against Ganymede's crust. Meanwhile Olaf prayed, swore, wept and jiggled all the compressed air jets at once.

Ganymede whirled and Jupiter was a wild blur. Perhaps it was the spectacle of Jupiter doing the shimmy that steadied the spinies. More likely it was the fact that they just didn't give a hang any more. Whatever it was, they halted, made lofty farewell speeches to one another, confessed their sins and waited for death…

The sleigh steadied and Olaf resumed his breathing once more. Only to stop again as he viewed the curious spectacle of the hills and solid ground up above, and black sky and swollen Jupiter down below.

It was at this point that he, too, made his peace with the eternal and awaited the end.

'Ossie' is short for ostrich, and that's what native Gany-medans look like, except that their necks are shorter, their heads are larger and their feathers look as if they were about to fall out by the roots. To this, add a pair of scrawny, feathered arms with three stubby fingers apiece. They can speak English, but when you hear them, you wish they couldn't.

There were fifty of them in the low purplewood structure that was their 'meeting hall.' On the mound of raised dirt in the front of the room - dark with the smoky dimness of burning purplewood torches fetid to boot - sat Commander Scott Pelham and five of his men..Before them strutted the frowziest Ossie of them all, inflating his huge chest with rhythmic, booming sounds.

He stopped for a moment and pointed to a ragged hole in the ceiling.

'Look!' he squawked. 'Chimney. We make. Sannycaws come in.'

Pelham grunted approval. The Ossie clucked happily. He pointed to the little sacks of woven grass that hung from the walls.

'Look! Stockies. Sannycaws put presets!'

'Yeah,' said Pelham unenthusiastically. 'Chimney and stockings. Very nice.' He spoke out of the corner of his mouth to Sim Pierce, who sat next to him: 'Another half-hour in this dump will kill me. When is that fool coming?'

Pierce stirred uneasily.

'Listen,' he said, 'I've been doing some figuring. We're safe on everything but the karen leaves, and we're still four tons short on that. If we can get this fool business over with in the next hour, so we can start the next shift and work the Ossies at double, we can make it.' He leaned back. 'Yes, I think we can make it.'

'Just about,' replied Pelham gloomily. 'That's if Johnson gets here without pulling another bloomer.'

The Ossie was talking again, for Ossies like to talk. He said:

'Every year Kissmess comes. Kissmess nice, evvybody friendly. Ossie like Kissmess. You like Kissmess?'

'Yean, fine,' Pelham snarled politely. 'Peace on Ganymede, good will toward men - especially Johnson. Where the devil is that idiot, anyhow?'

He fell into an annoyed fidget, while the Ossie jumped up and down a few times in a thoughtful sort of manner, evidently for the exercise of it. He continued the jumping, varying it with little hopping dance steps, till Pelham's fists began making strangling gestures. Only an excited squawk from the hole in the wall dignified by the term 'window' kept Pelham from committing Ossie-slaughter.

Ossies swarmed about and the Earthmen fought for a view.

Against Jupiter's great yellowness was outlined a flying sleigh, complete with reindeers. It was only a tiny thing, but there was no doubt about it. Santa Claus was coming.

There was only one thing wrong with the picture. The sleigh, 'reindeer' and all, while plunging ahead at a terrific speed, was flying upside down.

The Ossies dissolved into squawking cacophony.

'Sannycaws! Sannycaws! Sannycaws!'

The scrambled out the window like so many animated dust-mops gone mad. Pelham and his men used the low door.

The sleigh was approaching, growing larger, lurching from side to side and vibrating like an off-center flywheel. Olaf Johnson was a tiny figure holding on desperately to the side of the sleigh with both hands.

Pelham was shouting wildly, incoherently, choking on the thin atmosphere every time he forgot to breathe through his nose. Then he stopped and stared in horror. The sleigh, almost life-size now, was dipping down. If it had been an arrow shot by William Tell, it could not have aimed between Pelham's eyes more accurately.

'Everybody down!' he shrieked, and dropped.

The wind of the sleigh's passage whistled keenly and brushed his face. Olaf's voice could be heard for an instant, high-pitched and indistinct. Compressed air spurted, leaving tracks of condensing water vapor.

Pelham lay quivering, hugging Ganymede's frozen crust. Then, knees shaking like a Hawaiian hula-girl, he rose slowly. The Ossies who had scattered before the plunging vehicle had assembled again. Off in the distance, the sleigh was veering back.

Pelham watched as it swayed and hovered, still rotating. It lurched toward the dome, curved off to one side, turned back, and gathered speed.

Inside that sleigh, Olaf worked like a demon. Straddling his legs wide, he shifted his weight desperately. Sweating and cursing, trying hard not to look 'downward' at Jupiter, he urged the sleigh into wilder and wilder swings. It was wobbling through an angle of 180 degrees now, and Olaf felt his stomach raise strenuous objections.

Holding his breath, he leaned hard with his right foot and felt the sleigh swing far over. At the extremity of that swing, he released the gravo-repulsor and, in Ganymede's weak gravity, the sleigh jerked downward. Naturally, since the vehicle was bottom-heavy due to the metal gravo-repulsor beneath, it righted itself as it fell.

But this was little comfort to Commander Pelham, who found himself once more in the direct path of the sleigh.

'Down!' he yelled, and dropped again.

The sleigh whi-i-ished overhead, came up against a huge boulder with a crack, bounced twenty-five feet into the air, came down with a rush and a bang and Olaf fell over the railing and out.

Santa Claus had arrived.