The Amulet of Samarkand

the parade ground, and as I flashed past, I caught a glimpse of a formidable company of spirits appearing within them, summoned at that moment by a troop of gray-uniformed magicians. The spirits were minor ones, glorified imps for the most part,[3] but en masse they would present problems. I hoped the flock of ravens would not land here.
     
    [3] The less powerful the being, the quicker and easier it is to summon. Most magical empires employ some magicians specially to rustle up whole cohorts of imps at short notice. Only the greatest empires have the strength in depth to create armies of higher entities. The most formidable such army ever seen was put together by Pharaoh Tuthmosis III in 1478 B.C. It included a legion of afrits and a motley group of higher djinn, of which surely the most notable was... No, modesty prevents my continuing.
     
    But the birds displayed no desire to halt; fear still carried them onward in a whirling course across the fortifications of the Tower. Several times they seemed to be heading for an outer wall; on each occasion they banked and turned back. Once I was tempted to make a break for it alone, but was discouraged by the appearance on the battlements of an odd blue-black sentry with four spider-like legs. I didn't like its look, and was too weary after my captivity and forced changes of form to risk its unknown power.
    At last, we came to yet another courtyard, surrounded on three sides by castle buildings and on the other by a steep bank of green grass rising up to a high wall. The ravens alighted on the bank and began to mill about, pecking at the ground aimlessly.
    Faquarl hopped over to me, one wing hanging away from his breast. It was still bleeding.
    "These birds are never going to leave the grounds," I said. "They get fed here."
    The raven nodded. "They've got us as far as they can, but it'll do. This is an outer wall. Over that and we're away."
    "Then let's go."
    "In a minute. I need to rest. And perhaps Jabor—"
    "Jabor's dead."
    "You know him better than that, Bartimaeus." Faquarl pecked at his wounded wing, pulling a feather away from the clotting blood. "Just give me a moment. That utukku! I wouldn't have guessed he had it in him."
    "Imps coming," I hissed. A battalion had scurried through an arch into the far corner of the yard and were fanning out to begin a meticulous survey of every brick and stone. We were still concealed within the flock of ravens, but not for long.
    Faquarl spat another feather onto the grass, where it briefly changed into a writhing strip of jelly before melting away. "Very well. Up, over, and out. Don't stop for anything."
    I gestured politely with a wing. "After you."
    "No, no, Bartimaeus—after you!" The raven flexed one large, clawed foot. "I shall be right behind you all the time, so please be original and don't try to escape."
    "You have a horrid, suspicious mind." The imps were creeping nearer, sniffing the ground like dogs. I took off and shot up toward the battlements at speed. As I drew level with them, I perceived a sentry patroling the walkway. It was a small foliot, with a battered bronze horn strapped to the side of his head. Unfortunately, he perceived me too. Before I could react, he had swiveled his lips to the mouthpiece of the horn and blown a short, sharp blast, which instantly triggered a wave of answering signals from along the wall, high and low, loud and soft, away into the distance. That did it: our cover was well and truly blown. I weaved at the sentry, talons grasping; he gave a squeak, lost his balance and tumbled backward over the edge of the wall. I shot across the battlements, over a steep bank of tumbled black rocks and earth, and away from the Tower into the city.
     
    No time to lose, no time to look back. I flapped onward, fast as I could. Beneath me passed a broad gray thoroughfare, heavy with traffic, then a block of flatroofed garages, a narrow street, a slab of shingle, a curve of the Thames, a wharf and steelyard, another street.... Hey! This wasn't too bad—with my customary panache, I was getting away! The Tower of London must already be a mile back. Pretty soon, I could...
    I looked up and blinked in shock. What was this? The Tower of London loomed ahead of me. Groups of flying figures were massing over the central keep. I was flying back toward it! Something had gone seriously wrong with my directions. In great perplexity I did a U-turn round a chimney and shot off again in the opposite direction.