The sailors were all young and healthy, and all of them were experienced sailors, known as those who had grown their sea-legs, extra legs to help them handle the pitching motion of the ship's deck in rough seas.
Billy hoped to grow his soon, encouraged by the many young sailors who berthed with him, all of whom had their sea-legs. Their berths were heavy with their extra pairs of legs, their two pairs of feet hanging out the ends of their berths, and Billy counted the days until he grew his own sea-legs. He would lie there in his lower berth as the young sailor in the berth above him climbed his four feet up the rungs of the berth ladder, up to his bunk.
They were definitely expert seamen, clambering their four legs up the robes and masts of the ship even as it swayed in the strong winds, and on sunny days when the work was done they sang sea chanties and danced to the tunes, happy dances done on four feet in the clean air and bright sun of the middle of the ocean.
They all encouraged Billy, who was making good progress becoming a good sailor, and they all agreed that he would make a fine four-legged sailor once he grew his sea-legs.
And sure enough, after a bad stretch of rough weather and high seas, Billy came through as a full-fledged sailor, helping with the chores as the ship pitched and tossed in high winds and crashing high waves. All the sailors were carrying out their orders, keeping the ship on course and afloat as water crashed over its bow, holding onto the wildly pitching decks with their four strong legs, keeping their balance and getting their work done no matter what the weather.
Billy's work was just as hard as theirs, and while nobody had any time to do anything but keep at it to help the ship make it through the storm, everyone could tell that Billy was a worthy mate, a fine sailor, and a hard-working one who could definitely pull his weight when the going got rough.
They all worked through the night, and made it through the storm well enough, but it didn't take long for the sailors to take advantage of the ensuing calm to get a little shut-eye, exhausted from the hard work of manning the ship in a storm.
But Billy slept the longest, not waking until he sensed others close around him, and sure enough, he awoke to the cheers of all the well-rested young sailors, who passed a bottle among them. “We'd known you'd have done it, and you did!” smiled his berthmate, and another cheer went up as Billy sat up in his berth, and lo and behold, he'd grown his four strong sea-legs!
All the young sailors sang a rousing sea chanty and danced on their four legs, grabbing Billy up to dance with them, and when it was offered him he took his swig from the bottle, gladly joining with the dancing four-legged sailors to celebrate his four feet, his four legs, his sea-legs!