“Yeah, I did. Sorry. But I’m really grateful. What else have you found out?”

“I ran a check on Jim Gowder this morning. Wife ill, sexually frustrated, young girl available in house. It’s classic. The record shows convictions for drunkenness, affray and failure to pay rates. But nothing sexual. Without any background of similar offenses, you might find it hard to get him in the frame after all this time, if you made it official.”

“Official? Went to the cops, you mean?”

It must have sounded as if she thought this was pretty wayout because he smiled and said gently, “You’ve taken a big step in that direction already, my dear. In fact, once I’m convinced an offense has taken place, I really ought to make it official myself.”

“What would happen if you did?”

“Coming from me, and concerning Illthwaite, probably nothing,” he said sadly. “But if you pressed, they’d have to take notice. On the plus side, once a prima facie case of sexual assault on a minor was established, they could require all likely suspects to supply DNA samples which would be checked against yours.”

“And on the minus?”

“Publicity,” said Melton. “Once the press got hold of this – and get hold of it they would; the modern police force has more leaks than a Welsh allotment – they’d be all over you, not to mention your family, as well of course as Illthwaite. Illthwaite has it coming, but it wouldn’t be pleasant for your folk. You’d need to think about it.”

Sam thought about it for long enough to eat two chocolate biscuits.

Finally she said, “You’re right. I’d need to talk to my pa and ma first. Could the police make people give samples?”

“If they’re alive and suspect, yes,” he said. “With Jim Gowder they’d need either to dig him up or get the twins to volunteer a sample. As for the curate, that’s more difficult as he was cremated. There’s always the stones he weighed himself down with, but they’re so smooth and they were under water for many hours, I’d be surprised if they helped.”

Something came into Sam’s mind then went out again as she said, “Doesn’t matter anyway. I’m pretty sure he’s not in the frame.”

“You are?” He looked at her curiously. “I’m surprised. He’s an obvious suspect, and in detective work, the obvious is so often right.”

“Can work the other way in math,” she said.

She wanted to tell him what she knew about the curate’s reasons for killing himself, but it wasn’t her secret to tell. She found she really was feeling bad about the old boy. He’d put himself out to help her, even bought some dark chocolate biscuits, and all she’d done was discount his number one suspect and let him know she’d discovered her grandmother’s identity without his help.

“That’s me done, I’m afraid,” said Melton rather sadly. “I had hoped to amaze you with my discoveries and my theories, but I fear I’ve brought you here for nothing.”

She said, “Thanks a bunch for all your trouble. And for the yummy biscuits.”

“Please, have another. Or two, if you like.”

“I’ll take one for the road,” she said, standing up and putting her hat back on. “Thanks again. Like I say, I need a long think before I make this official. I started it and it feels like I ought to see it through myself.”

“Your decision,” he said. “But tread carefully, my dear, before you start throwing accusations around. Get it right, someone could turn nasty. Getting it wrong can be nasty too. Remember what happened here in Candle Cottage. I still feel that poor devil’s pain some dark nights when I’m sitting here alone. Good job I don’t believe in ghosts!”

“Me neither,” said Sam.

On the other hand, she thought, Mig Madero probably didn’t believe in Hilbert space. And his spooks had got him as far along the path of revelation as her calculus.

At the front door, they stood together on the threshold and enjoyed the touch of the sun on their faces.

“Another couple of months and I’ll be in permanent shadow,” said Melton.

He saw the expression on her face and laughed.

“No, my dear, I’m not being morbid. I just mean that once we get into November, the sun never gets high enough to touch this end of the valley. It might bother some people, but I don’t mind. Unless you lose it for a space, you can never feel the delight I feel when quite suddenly early in March I look out to see the first finger of sunlight touching my garden.”

“That’s lovely,” exclaimed Sam. Impulsively she leaned forward and kissed the old man’s dry cheek.

“Careful,” he said. “You don’t want to shock the vicar.”

“What he doesn’t see won’t harm him.”

“God sees everything and the vicar has a direct line to God.”

“You don’t like him?” asked Sam, detecting satire.

“On the contrary, I think he’s a very decent man. Compared with his father, whose main concern was what was going to happen to us miserable sinners after death, Rev. Pete concentrates on taking care of the living. He’ll be missed when he’s gone. And no more Swinebanks to follow. We’ll probably get some menopausal matron – no offense.”

“None taken,” said Sam. “You said we. Like you feel you’re one of them.”

“After all my years here, how else should I feel?” he said, smiling.

“Yeah.” She found herself thinking indignantly, it’s not right he’s never been told. Everyone’s got a right to know the truth about what most concerns them. Someone ought to have told him long ago. Ought to tell him now.

His bright little eyes were fixed on her face as though seeing her thoughts.

As she opened her mouth – not yet knowing exactly what was going to come out, a not uncommon situation when the indignant fit was upon her – he put one finger up almost to her lips and said, “Yes, my dear, I shall live out the rest of my days here quite happily, an itch on the Illthwaite bottom which they might from time to time feel like scratching but which they will hardly use surgery to remove. After all, if I weren’t here, keeping an eye on things, what reason would I have to get up in the morning? And where would I go? Retire to a villa in Spain perhaps to shrivel up in permanent sunshine?”

A villa in Spain!

He knows! How can he know? He can’t know!

The thoughts tumbled across Sam’s mind like leaves in a west wind. Again she opened her mouth, again not knowing what she would say, and again he was there first.

“Goodbye, my dear. And good luck. And use your ears. Fingerprints, DNA, these are fine, but frequently all the forensic us hardworking detectives get is words. What people say, what they don’t say, what they say other people say. Look for inconsistencies. These too are tracks. The muddier we try to make them, the easier they are to follow.”

Was he warning her off? She didn’t know, couldn’t ask. And in any case his advice, and his comments about the vicar, had brought something else to mind.

An inconsistency.

She said, “Just one thing more. About Sam Flood, the curate. Young Pete’s statement said he was in his room and the curate shouted up to him that the Bible class was canceled. That was all the conversation they had, right?”

“Yes, I think so. In fact I’m sure so.”

“And he didn’t mention anyone else coming to the house after lunch?”

“No, definitely not. Why do you ask?”

“Just getting things straight in my mind. No big deal.”

Which was probably true. If God was the last prime number, human beings were the first irrational. No, worse than that. The square root of two was an irrational number, but at least you knew that if you squared it, you got back to two. And if you wanted to actually see it, all you had to do was draw a pair of one-inch lines at a right angle. Human behavior, however, subscribed to no such laws. An inconsistency in a mathematical proof was fatal. But inconsistency in human evidence could mean nothing at all.

Or, as in the case of Gracie and the year of sailing, everything.