He punctuated this last thought with such a deep sigh that a house sparrow singing nearby stopped and rushed home to be with his family.     The sun was dropping slowly from sight, and stripes of purple and orange and crimson and gold piled themselves on top of the distant hills. The last shafts of light waited patiently for a flight of wrens to find their way home, and a group of anxious stars had already taken their place.     The last colours slowly faded from the western sky, and as they did, one by one the instruments stopped, until only the bass fiddles, in their sombre slow movement, were left playing the night and a single set of silver bells brightened the constellations.     'But what pleasure to lead my violins in a serenade of spring green or hear my trumpets blare out the blue sea and then watch my oboes tint it all in warm yellow sunshine. And rainbows are the best of all -- and blazing neon signs, and the soft, muted tones of a foggy day. We play them all.'     '...everything from the tender moss in a pavement crack to the glow of the farthest star...'     'Have you ever heard a blind octopus unwrap a Cellophane-covered bathtub?' he enquired again as the air was filled with a loud, crinkling, snapping sound.     'LOOK CAREFULLY  AND WE  WILL TELL YOU  OF OUR TERRIBLE MISFORTUNE'.     'Now remember, they're not for eating, but for listening, because you'll often be hungry for sounds as well as food. Here are street noises at night, train whistles a long way off, dry leaves burning, busy department stores, crunching toast, creaking bedsprings, and, of course, all kinds of laughter. There's a little of each, and in far-off lonely places I think you'll be glad to have them.'     'Certainly not! They're all the wrong way. Just because you have a choice, it doesn't mean that any of them has to be right.'     And striding towards them came a figure who could only have been a Mathemagician.     'One of the nicest things about mathematics, or anything else you might care to learn, is that many of the things which can never be, often are.'     The Mathemagician nodded knowingly and stroked his chin several times. 'You'll find', he remarked gently, 'that the only thing you can do easily is be wrong, and that's hardly worth the effort.'     Milo tried very hard to understand all the things he'd been told, and all the things he'd seen, and, as he spoke, on curious thing still bothered him. 'Why is it,' he said quietly, 'that quite often even the things which are correct just don't seem to be right?'     'For you often learn more by being wrong for the right reasons that you do by being right for the wrong reasons.'     The late afternoon sun had turned from a vivid yellow to a warm lazy orange, and it seemed almost as tired as he was.