In spite of the gravity of their discussion, Monk found himself smiling at her. Cardman would have been horrified. She was perhaps a year or two older than he. Monk wondered what the relationship had been between them. Superficial? Or had their station in life prevented what would have been a testing but rewarding love?

He thrust the notion from his mind. "Mr. Alan Argyll was different?" he asked. "And was Mrs. Argyll at all like her sister?"

Mrs. Kitching's face hardened. "Mr. Alan's a very clever man, a lot cleverer than Mr. Toby realized," she answered without hesitation. "Mr. Toby might have thought he'd get the upper hand in time, but he wouldn't. Miss Mary told me that. Not that I didn't think so myself, just seeing them in the withdrawing room. Miss Jenny's a realist, never was a dreamer like Miss Mary. Easier to get along with. Never asks for the impossible or fights battles she can't win. Been a good wife to Mr. Alan. I suppose Mr. Toby thought Miss Mary'd be the same. Well, he thought wrong!" She said that last with considerable satisfaction. Then she remembered again that Mary was dead. The tears washed down her cheeks, and this time she was unable to control them.

Monk was embarrassed, and angry with himself for being so. Why should he? Mrs. Kitching's was an honest grief; there was nothing in it to apologize for.

He thanked her with deep sincerity and then excused himself.

By midday Monk was back across the city at the construction works again. This time he found Aston Sixsmith aboveground and able to speak more easily. There was no point in asking him about Mary. He would be unlikely to know anything of use, but he might know something of the relationship between the two brothers. He would have to be far more circumspect here. Sixsmith would be loyal out of the need to guard his job, even if not from personal regard.

"Was Mr. Toby Argyll aware of Havilland's fear of tunnels?" he asked. They were standing on the bare clay at least a couple of hundred yards from the nearest machine, and the noise of it seemed distant in the brief winter sun.

Sixsmith pulled his wide mouth tight. "I'm afraid we all were. If you were watching the man, you couldn't miss it. And to be honest, Mr. Monk, it's part of your job to look for the man who'll crack because he's a danger to everyone else, especially if he's in charge of anything. I'm sorry." His highly expressive face was touched with sadness. "I liked Havilland, but liking's got nothing to do with safety. If he'd gone barmy or started telling the men that there was a river going to break through the walls, or choke-damp in the air, or a cave-in coming, he'd have started a panic. God knows what could have happened." He looked at Monk questioningly to see if he understood.