It was the office key.

"By Jove, you were right."

Antony felt in the bag again, and then turned it gently upside
down on the grass. A dozen large stones fell out--and something
else. He flashed down his torch.

"Another key," he said.

He put the two keys in his pocket, and sat there for a long time
in silence, thinking. Bill was silent, too, not liking to
interrupt his thoughts, but at last he said:

"Shall I put these things back?"

Antony looked up with a start.

"What? Oh, yes. No, I'll put them back. You give me a light,
will you?"

Very slowly and carefully he put the clothes back in the bag,
pausing as he took up each garment, in the certainty, as it
seemed to Bill, that it had something to tell him if only he
could read it. When the last of them was inside, he still waited
there on his knees, thinking.

"That's the lot," said Bill.