The Amulet of Samarkand

raised his hand once more, he scooped up as many cubes as he could and disappeared behind a neighboring bookcase. The second plasm bolt struck just behind him.
    He paused for a moment. Beyond the bookshelves, the old magician made a clucking noise with his tongue. "What are you doing? Do you plan to toss more mites at me?"
    Nathaniel glanced at the objects in his hand. Not mites, but scarcely any better. Prague Cubes: minor conjuror's tricks peddled by low-caste magicians. Each cube was little more than a mite bottled up inside a metal shell with a variety of mineral powders. When released with a simple command, mite and powders combusted in an amusing way. Silly diversions, nothing more. Certainly not weapons.
    Each cube had a paper wrap stamped with the famous distilling-glass logo of the alchemists of Golden Lane. They were old, probably nineteenth century. Perhaps they would not work at all.
    Nathaniel picked one and tossed it, wrapping and all, over the top of the shelves.
    He shouted the Release Command.
    With a brilliant shower of silver sparkles and a tinny melody the imp inside the cube combusted. A faint but unmistakable fragrance of lavender filled the gallery.
    He heard the old magician burst into a hearty chuckle. "How charming! Please—some more! I wish to smell my best when we take over the country! Do you have rowan flavor? That would be my favorite!"
    Nathaniel selected another cube. Party gimmicks or not, they were the only things he had.
    He could hear the squeaking of the old man's shoes as he shuffled down the gallery toward the end of his aisle. What could he do? On either side, bookcases blocked his way out.
    Or did they? Each shelf was open-backed: on every row, he could see above the tops of the books into the next aisle. If he pushed himself through...
    He tossed the next cube and ran at the shelf.
     
    Maurice Schyler rounded the corner, his hand invisible inside its wavering bulb of force.
    Nathaniel hit the second shelf of books like a high jumper clearing a bar. He muttered the Release Command.
    The cube exploded in the old man's face. A starburst of purple sparks zipped and spun, high as the ceiling; a nineteenth-century Czech marching song rang out briefly in accompaniment.
    In the next aisle along, fifty books crashed down like a falling wall. Nathaniel sprawled on top of them.
    He felt, rather than saw, the third bolt of plasm destroy the aisle behind him.
    The magician's voice now carried a slight note of irritation. "Little boy—time is short! Stand still, please." But Nathaniel was already on his feet and hurtling toward the next shelf. He was moving too fast to think, never allowing himself a moment's pause, lest his terror rose up to overwhelm him. His one aim was to reach the door at the far end of the gallery. The old man had said there was a pentacle there.
    "John—listen!" He landed on his back in the next aisle, amid a shower of books. "I admire your resolve." A leather-bound dictionary fell against the side of his head, making bright lights twinkle across his vision. He struggled upright. "But it is foolish to seek revenge on your master's behalf." Another burst of magical force: another section of shelving vanished. The room was filled with thick, acrid smoke. "Foolish and unnatural. I myself killed my own master, long ago. Now, if your Underwood had been a worthy man, I would understand it." Nathaniel threw the third cube behind him; it bounced harmlessly against a table and did not go off. He had forgotten to say the command. "But he was not a worthy man—was he, John? He was a driveling idiot. Now you will lose your life for him. You should have stayed away."
    Nathaniel had reached the final aisle. He was not far from the door at the end of the room—it was a few strides off. But here, for the first time, he stopped dead. A great anger swelled inside him and damped down his fear.
    Shoes squeaked softly. The old man shuffled back up the gallery, following the trail of scattered books, checking each side-aisle as he went. He saw no sign of the boy. Drawing near the door, he turned into the final aisle, hand raised at the ready—
    He clicked his tongue in exasperation. The aisle was empty.
    Nathaniel, who had silently clambered back through the shelves to the previous aisle and had now crept up behind him, thus had the element of surprise.
    Three cubes hit the magician at once and exploded together at a single command. They were a lime-green Catherine Wheel, a