“Just to Gillicombe.”

“Why?”

“To do some shopping, go to the library.”

The bitterness in the exchange was embarrassing. There was a silence.

Then, changing the subject, John said: “ I meant to tell you before, George. I told you that I thought somebody was up before me on Saturday morning. I remember now what made me think so. It isn’t much. There were muddy footprints on the hall floor. Just one set of wet footprints. I came in after hoisting the cone and I noticed them then.”

“Can you visualize where the footsteps went?”

“Oh yes. Only as far as the coat rack. They were made by that spare pair of wellies. You know, the ones which went with the duffel coat that the police took away.”

“Are you sure?”

“Yes. The boots were lying on their sides, on the floor. I can remember quite clearly.”

“Did the police take the wellingtons with them?”

“I don’t think so.”

“Let’s go to see.”

The boots were still there. George looked at them carefully, without touching them. The size number had been worn from the inside and from the tread, but they were big. He could have worn them, and he had larger than average feet. The boots were lying on their sides, so he could see the soles. They were worn smooth and nothing clung to the rubber but the red sand of the track.

“At least the murderer had the decency to take his boots off here,” John said, with an attempt at humour, “which is more than Doctor Derbyshire bothers to do. On the morning of Charlie’s death he walked up the stairs and left half the garden on the floor.”

“Did he? I wonder where he had been. There’s not a lot of open ground on the island. What time was it?”

“I’m not sure exactly. It was when I was on the way back to phone the police.”

“Did you tell Superintendent Savage about the wellingtons?”

“No. I only remembered this morning. Do you think I should?”

“Yes. You see, nobody admitted to being up before you. So it is important. The boots were probably worn by the murderer.”

The men wandered, through habit, into the ringing room. Molly followed them. They did not explain what happened there, but she had been in observatories with George before. She walked around reading the notices of ringing recovery pinned on to the notice board, the old school timetables, the rotas for washing up and cleaning. She was not bored. She was listening. John was showing George some photographs of birds in the hand.

“I suppose Savage asked you about chloroform,” George said.

“Yes. He made me feel a bit guilty that it was here, but I didn’t bring it on to the island. The teacher of last term’s A-level group was using it, I think. The schools have the run of the place while they’re here. I’ve seen the jar in the cupboard, but it never occurred to me that it might be dangerous. People here are usually responsible.”