“You are in the library, sir,” said Lucas. “I think you fainted.”

“Help me up. I need to talk to Norrell.”

“But I told you already, sir …”

“No,” said Childermass. “You are wrong. He must be here. He must be. Take me upstairs.”

Lucas helped him up and out of the room, but when they reached the stairs he very nearly collapsed again. So Lucas called for Matthew, the other footman, and together they half-supported, half-carried Childermass to the little study upon the second floor where Mr Norrell performed his most private magic.

Lucas opened the door. Inside, a fire was burning in the grate. Pens, pen-knives, pen-holders and pencils were placed neatly in a little tray. The inkwell was filled and the silver cap placed on it. Books and notebooks stood stacked neatly or tidied away. Everything was dusted and polished and in perfect order. Clearly Mr Norrell had not been there that morning.

Childermass pushed the footmen away from him. He stood and gazed at the room in some perplexity.

“You see, sir?” said Lucas. “It is just as I told you. The master is at the Admiralty.”

“Yes,” said Childermass.

But it made no sense to him. If the eerie magic was not Norrell’s, then whose could it be? “Has Strange been here?” he asked.

“No, indeed!” Lucas was indignant. “I hope I know my duties better than to let Mr Strange in the house. You still look queer, sir. Let me send for a physician.”

“No, no. I am better. I am a great deal better. Here, help me to a chair.” Childermass collapsed into a chair with a sigh. “What in God’s name are you both staring at?” He waved them both away. “Matthew, have you no work to do? Lucas, fetch me a glass of water!”

He was still dazed and dizzy, but the sick feeling in his stomach had lessened. He could picture the landscape in every detail. The image of it was fixed in his head. He could taste its desolation, its otherworldliness, but he no longer felt in danger of losing himself in it. He could think.

Lucas returned with a tray with a wine-glass and a decanter full of water. He poured a glass of water and Childermass drank it off.

There was a spell Childermass knew. It was a spell to detect magic. It could not tell you what the magic was or who was performing it; it simply told you whether there was any magic occurring or not. At least that was what it was supposed to do. Childermass had only ever tried it once and there had been nothing. He had no way of knowing whether or not it worked.

“Fill the glass again,” he told Lucas.

Lucas did so.

This time Childermass did not drink from the glass. Instead he muttered some words at it. Then he held it up to the light and peered through it, turning slowly until he had surveyed every part of the room through the glass.