Ark Angel

moment that your centre of mass is not directly above it. One wobble and gravity will do the rest.
    But a long pole increases what is called the rotational inertia of the tightrope artist. It makes it more difficult to fall. And if you add enough weight to each end, you will actually shift your centre of gravity below the wire. This was what Alex had done with the two buckets. Provided he didn’t drop the pole, he would find it almost impossible to lose his balance. He had seen toys that worked on the same principle. It should be easy.

    At least, that was the theory. Alex took a step. He had one foot on the very edge of the brickwork and one foot on the metal cable. All he had to do was lean forward, transferring his weight from one foot to the other, and he would be walking the tightrope. If the laws of physics worked, he would make it across. If they didn’t, he would die. It was as simple as that.
    He took a deep breath and launched himself off the building.
    He could feel the pole flexing as the buckets hung down, one on each side. For a terrifying moment the world seemed to lurch sideways and he was certain he was about to fall. But he forced himself not to panic.
    He clutched the pole more tightly against his chest and focused on the cable ahead of him. Briefly he closed his eyes, willing himself not to fight for balance, to let the laws of physics guide him.
    And it worked. He wasn’t falling. He could feel the cable cutting into his feet but miraculously he was stable. Now—how many steps to the other side? The flames were warming his back. It was time to move.
    One step after another, he made his way across. He wanted to look down. Every nerve in his body was screaming at him to do just that, and his neck and spine were rigid with tension. But that was the one thing he must not do. He tried to imagine that he was back on the sports field at Brookland School. He had walked along the painted white lines often enough. This was exactly the same—just a bit higher up.
    He was about halfway across when things began to go wrong. And they went wrong spectacularly.
    First, the police and fire engines arrived. Alex heard the screams of the sirens directly beneath him and, before he could stop himself, he looked down. It was a mistake. He was no longer walking across a sports field. He was standing on a wire, insanely far above the ground. He saw people in uniform pointing up at him and shouting; he could just about hear their voices. One of the fire trucks was extending its ladder towards him but he doubted it would reach him in time.
    The whole world began to spin. He felt a rush of panic that seemed to dissolve every muscle in his body and left him so weak that he thought he would faint. At the same time, the wind rose and the banner began to flutter like the sail of a yacht, the cable swaying from side to side. Alex knew that only the weights on the ends of the pole were keeping him upright. He was paralysed. There was nothing he could do.
    And that was when the rooftop exploded. The flames had finally broken free. A fireball burst through the tarmac. The police and firemen dived for cover as bricks and pieces of metal rained down. The whole tower block was close to collapse. Alex felt a vibration travel up through his body and realized with horror that the metal stanchion holding the top cable was about to come loose. He couldn’t wait for the firemen to reach him. He had perhaps seconds left.
    The shock of the explosion broke his paralysis. Alex ran, pushing against the pole, like a sprinter breaking through the finishing line. The buckets swung madly, held fast by the bandages. Another explosion, louder this time. He didn’t dare look round.
    The other building was getting nearer but it still wasn’t near enough. His arms were aching, barely able to hold the heavy weight. The cable was cutting into his feet. He was being battered by the wind. He wasn’t going to make it. And then the cable snapped. Alex heard a sound like a crack of a whip and knew that his lifeline had been severed. With a cry, he dropped the pole and threw himself forward, reaching out for the roof just a few metres away. The cable and the banner crumpled under his feet. His hands missed the edge of the building and he began to plunge down. But now he was tangled up with the banner; it was folding itself around him. Alex grabbed hold of the material and gasped as he crashed into the wall. His feet were dangling in space. The cable