“Yes. A—a great mystery.” Perplexed, Ganil stared down into his beer. Mede smiled and said in his soft voice, “I know. Drink up, now. I think you ought to have an Apothecary look at that burn.” Ganil obediently followed him out into the evening, into the narrow streets thronged with pedestrians, horse-carts, ox-carts, chuffing motor-carts. In the Merchantsplace the booths of the artisans were being closed for the night, and down High Street the great doors of the Shops and Lodges were already barred. Here and there the overhung, elbowing houses were parted by the blank yellow façade of a temple, marked with one plain circle of polished brass. In the dull, brief summer twilight under the unmoving clouds the black-haired, bronze-skinned people of the Common Day crowded and idled and pushed and talked and cursed and laughed, and Ganil, dizzy from fatigue and pain and strong beer, kept close beside Mede as if, for all his own new Masterhood, this blue-eyed stranger were his only guide.

“XVI plus IXX,” Ganil said impatiently, “what the devil, boy, can’t you add?” The apprentice flushed red. “Isn’t it XXXVI, then, Master Ganil?” he asked feebly. For answer Ganil jammed one of the rods the boy had been machining into its place in the steam engine that was being repaired; it was too long by an inch.

“It’s because my rule of thumb’s so long, sir,” the boy said, displaying his knobby hands. The distance between first and second thumb-joint was in fact unusually long. “So it is,” Ganil said. His dark face darkened. “Very interesting. But it doesn’t matter how long your inch is so long as you use it consistently. And what matters, you blockhead, is that XVI and IXX don’t make XXXVI, never have, never can, never will till the world ends—you incompetent gentile!”

“Yes, sir. It’s so hard to remember, sir.”

“It’s intended to be hard to remember, Wanno Prentice,” said a deep voice: Lee the Shopmaster, a fat deep-chested man with bright black eyes. “Come over here a minute, Ganil.” Leading him to a quieter corner of the great workshop, Lee went on cheerfully, “You’re a bit impatient, Master Ganil.”

“Wanno should know his addition-tables.”

“Even Masters forget an addition now and then, you know.” Lee patted Ganil’s shoulder in a fatherly way. “Why, you sounded for a moment there as if you expected him to compute it!” He laughed aloud, a fine bass laugh through which his eyes gleamed merrily and with infinite shrewdness. “Take it easy, that’s all. . . . I understand you’re coming for dinner next Altarday Eve?”

“I took the liberty—”