The second measurer reached the holding pond, and he stopped there a long time. The pond lay in the low corner of the field, full and quiet, its surface catching the morning light, and the staggered gates that let the water out in turns stood open in their sequence, exactly as Selma's rotation called for. The man measured the pond's depth at three points, and he measured the outflow, and he wrote it all down, and then he walked the lower rows of the orchard, where the trees stood green and heavy with fruit in a summer when every other orchard in the valley was already showing the yellow at the leaf edges that meant thirst.
When the second measurer came back up the ditch, his face had changed. The certainty he had arrived with was gone, replaced by something Ketchum recognized: the look of a man who has measured carefully and found an answer he did not expect and does not know what to do with.
"Well?" Halden said, before the man could reach them. "What does it say?"
The second measurer looked at his book, and then at Ketchum's book, and then at the ditch, as if he hoped the three of them might disagree and give him somewhere to stand.
"It says what his book says," the man said, finally. "Within a finger's width. The trial field is using less water than the flood fields above it. And the trees are in better condition. I measured it twice at the third station because I did not believe the first reading."
A silence fell over the field, the kind that comes when everyone understands the same thing at once and none of them wants to be the first to say it.
Halden did not look at the second measurer. He looked at Selma.
"Then the figures are wrong somewhere else," he said. "If the ditch says one thing and the books say another, the books are where a person would hide it."
Selma did not flinch. Ketchum had watched her, over the course of this summer, learn to take a blow without stepping back, and he admired it the way he admired any well-built thing: not for its beauty, but for the fact that it held.
"Which books, Mr. Halden?" she asked.
"Yours," Halden said. "Six years of numbers, written by one hand, in books nobody else kept. A woman who wants a valley to change its water will write the numbers that change it. I am not saying you lied, Miss Ivers. I am saying no one can prove you did not."
It was a clever attack, and Ketchum knew it the moment he heard it, because it did not argue with the ditch at all. It argued with the only witness who could not speak for herself: the past. Selma's notebooks reached back six years, to seasons when no one else had been watching the creek the way she had. If Halden could make the valley doubt those years, he could make them doubt the trial too, because the trial rested on the claim that Selma knew what the creek had always done, and therefore knew what it could be made to do now.
Eben Yates took a step forward, and his voice, when it came, was low and rough, the voice of a man who does not like to speak in front of others and is doing it anyway.
"Then prove it another way," Eben said. "There are other records in this valley besides hers."
Halden turned on him. "Whose? Yours? You gave her your field. You are hardly a disinterested witness, Yates."
"Not mine," Eben said. "The creek's."
He walked to the headgate post, and he laid his hand on it, on the old timber that had stood there longer than any man in the valley had farmed beside it, and he pointed to the side of the post that faced away from the road, where the wood was dark with weather and age.
Ketchum had seen the post a hundred times and had never looked at that side of it closely. Now, following Eben's hand, he saw what he had been walking past for eleven years: a series of shallow cuts in the wood, made with a knife, at different heights, each one darkened by time, each one as deliberate as a line in a book.