The mighty-thewed barbarian, Conan, was a native of Ultima Thule, that cold, drear land to the uttermost North. There, amid snow-clad mountains, his tribe fought ice-trolls and raided neighboring lands. It was a living.
But like many a small-town boy, Conan yearned to get the hell out of his parents' yurt. So one day he strapped sword to waist, threw a bear-fur cloak over his naked chest, and stalked off into the snows, to find his destiny.
Three days into the frozen wastes, he was awakened by a hum outside his snow-cave. Making certain that his sword was secure within its sheath, he burrowed his way out and was astonished to see a metal tower where none had been the day before.
A round doorway opened in the side of the tower and a man—weak and pink, like the city-dwellers of the South—popped his head out. "Ho—primitive savage!" he shouted. "Have you seen any monazite hereabouts? Or bastnäsite?"
"Eh?" said the heroic adolescent.
"Thulium-containing ores!" Nimble as a monkey, the little man dropped to the ground. "Thulium is extremely hard to isolate in my world, so I invented the alternate-past machine to search for alternate-ores from which it might be more readily extracted." He whipped out a small metal box that beeped and peered intently at it. "Say! It looks like your sword is made of an alloy containing a good fourteen percent thulium. Would you mind giving me a closer look at its blade?"
Conan drew the sword from its sheath. "I suppose," he said slowly, "that something like that could be arranged."
There were, disappointingly enough, no gold bars or precious gems in the little wizard's tower. But his boots fit well enough. They lasted him all the way to the jungles of Kush before falling apart. For the rest of his life—even after he became emperor—Conan was to regret not asking where they'd come from, before killing the wizard.