"I know what I'm saying. The red cup was his," said Mr. Satterthwaite, "and the red cup's broken. It's been replaced with a blue one. He doesn't know the red from blue, does he?"
Dr. Horton looked puzzled. "D'you mean - d'you mean like Tom?"
"Tom Addison. He's color-blind. You know that, don't you?"
"Oh yes, of course. We all know that. That's why he'd got odd shoes on today. He never knew red from green."
"This boy is the same."
"But - but surely not. Anyway, there's never been any sign of it in - in Roland."
"There might be, though, mightn't there?" said Mr. Satterthwaite. "I'm right in thinking - Daltonism. That's what they call it, don't they?"
"It was a name they used to call it by, yes."
"It's not inherited by a female, but it passes through the female. Lily wasn't color-blind, but Lily's son might easily be colorblind."
"But my dear Satterthwaite, Timothy isn't Lily's son. Roly is Lily's son. I know they're rather alike. Same age, same-colored hair and things, but - well, perhaps you don't remember."
"No," said Mr. Satterthwaite, "I shouldn't have remembered. But I know now. I can see the resemblance too. Roland's Beryl's son. They were both babies, weren't they, when Simon remarried. It is very easy for a woman looking after two babies, especially if both of them were going to have red hair. Timothy's Lily's son and Roland is Beryl's son. Beryl's and Christopher Eden's. There is no reason why he should be colorblind. I know it, I tell you. I know it!"
He saw Dr. Horton's eyes go from one to the other. Timothy, not catching what they said but standing holding the blue cup and looking puzzled.
"I saw her buy it," said Mr. Satterthwaite. "Listen to me, man. You must listen to me. You've known me for some years. You know that I don't make mistakes if I say a thing positively."
"Quite true. I've never known you to make a mistake."
"Take that cup away from him," said Mr. Satterthwaite. "Take it back to your surgery or take it to an analytic chemist and find out what's in it. I saw that woman buy that cup. She bought it in the village shop. She knew then that she was going to break a red cup, replace it by a blue and that Timothy would never know that the colors were different."
"I think you're mad, Satterthwaite. But all the same I'm going to do what you say."
He advanced on the table, stretched out a hand to the blue cup.
"Do you mind letting me have a look at that?" said Dr. Horton.
"Of course," said Timothy. He looked slightly surprised.
"I think there's a flaw in the china, here, you know. Rather interesting."
Beryl came across the lawn. She came quickly and sharply.
"What are you doing? What's the matter? What is happening?"
"Nothing's the matter," said Dr. Horton, cheerfully. "I just want to show the boys a little experiment I'm going to make with a cup of tea."
He was looking at her very closely and he saw the expression of fear, of terror. Mr. Satterthwaite saw the entire change of countenance.
"Would you like to come with me, Satterthwaite? Just a little experiment, you know. A matter of testing porcelain and different qualities in it nowadays. A very interesting discovery was made lately."
Chatting, he walked along the grass. Mr. Satterthwaite followed him and the two young men, chatting to each other, followed him.
"What's the Doc up to now, Roly?" said Timothy.
"I don't know," said Roland. "He seems to have got some very extraordinary ideas. Oh well, we shall hear about it later, I expect. Let's go and get our bikes."
Beryl Gilliatt turned abruptly. She retraced her steps rapidly up the lawn towards the house. Tom Addison called to her:
"Anything the matter, Beryl?"
"Something I'd forgotten," said Beryl Gilliatt. "That's all."
Tom Addison looked inquiringly towards Simon Gilliatt.
"Anything wrong with your wife?" he said.
"Beryl? Oh no, not that I know of. I expect it's some little thing or other that she's forgotten. Nothing I can do for you, Beryl?" he called.
"No. No, I'll be back later." She turned her head half sideways, looking at the old man lying back in the chair. She spoke suddenly and vehemently. "You silly old fool. You've got the wrong shoes on again today. They don't match. Do you know you've got one shoe that's red and one shoe that's green?"
"Ah, done it again, have I?" said Tom Addison. "They look exactly the same color to me, you know. It's odd, isn't it, but there it is."
She went past him, her steps quickening.
Presently Mr. Satterthwaite and Dr. Horton reached the gate that led out into the roadway. They heard a motor bicycle speeding along.
"She's gone," said Dr. Horton. "She's run for it. We ought to have stopped her, I suppose. Do you think she'll come back?"
"No," said Mr. Satterthwaite, "I don't think she'll come back. Perhaps," he said thoughtfully, "it's best left that way."
"You mean?"
"It's an old house," said Mr. Satterthwaite. "And an old family. A good family. A lot of good people in it. One doesn't want trouble, scandal, everything brought upon it. Best to let her go, I think."