clothes werenât part of the Burra so they didnât do things for themselves. As soon as heâd got his anorak on, one of his blankets wriggled up and wrapped itself around his shoulders like a cloak. He patted his mattress goodbye and followed the Burra to the stairs. The cavern seemed to have gone fast asleep, as though almost all the âlifeâ that had kept it humming and twitching had left.
He was glad of the blanket when they got outside. It was bitter cold, with a black sky full of sharp little stars. Down by the lake he could hear a pump still chugging, but everything else seemed still. The Burra took his elbow to guide him down the path. When they got to the trip wire a faint light shone so that he could see to step over it. Now he could hear the plop and suck of bubbles rising in the lake and smell the stinking gas.
At the lakeâs edge the light shone again, just enough for James to see the edge of the basket thing.
âIn we get,â said the Burra.
James climbed over and picked his way through a jumble of things from the cavern to a clear space. The basket creaked at every step, and something else answered with fainter creaks above him. When he had settled he looked up, but could see nothing but blackness. No stars, even. Something huge was blotting out the sky, stirring a little as the breeze off the sea shifted it to and fro, and creaking as the immense net of knots and cords that held it in place took the strain.
The pump stopped. With a series of plops the tubes fell clear. Rustling whispers began as ropes untied themselves all around. In a sudden patch of quiet James heard scurryings from up the path, the clink of metal on rock, a squeak of challenge.
The last ropes fell free, timing it almost perfectly, so that the basket scarcely swayed as the Burraâs homemade airship floated silently up through the night.
Chapter 9: Over the Mountains
The wind blew steadily from the sea, pushing the airship inland. James could see the peaks ahead by the jagged line where the stars ended and there was only blackness below them.
It became colder as the airship rose. He shivered, and immediately another blanket came slithering along and wrapped itself around him. When he moved, the basketwork beneath him changed shape to make him comfortable. He had been wrong about the airship being home-made, he realized. It was home-grown, more like. It was all alive, the way the cavern had been alive. Somehow the Burra had managed to become an airship in order to go exploring.
âWhen are you going to start your engine?â he said.
âNot until we have to.â
âWhat does it run on?â
âFractionated by-products formed in the extraction of hydrogen from sewage gas.â
âHow did you know how?â
âWe thought it up with our computer.â
âThatâs brilliant. Have you brought the computer with you?â
âOf course. The whole trip would be impossible without it.â
âWhat will happen when the gulls see us?â
âIt will be all right.â
As the airship climbed, the mountains climbed too. It was difficult to see with everything so black, but sometimes James felt that the harsh slope was only just below them, although a moment before they had seemed to be floating miles above it. There was almost no wind. Or rather the airship was moving with the wind, so though it might be rushing along, the air around it seemed still.
Suddenly, almost straight ahead, James saw the glitter of starlit snow.
âLook out!â he yelled.
The noisy motor started before the shout was over. A propeller whumped at air. Slowly the ship swung sideways, almost grazing the cliff. The basket rocked violently where the wind buffeted into the mountain. The ship swung on until the nose pointed into the wind. Now every rope and cord shrieked in the streaming air as the engine slowly threshed their way out of danger.
As soon as they were clear it slowed,