Baley said, “I’ll see her myself later. View her, I mean.” He stared thoughtfully at Daneel. “Do you think she has any connection with this crime?”

“Apparently not a direct connection, Partner Elijah.”

“Does that imply there might be an indirect connection?”

“She might have persuaded someone else to do it.”

“Someone else?” Baley asked quickly. “Who?”

“That, Partner Elijah, I cannot say.”

“If someone were acting for her, that someone .would have to be at the scene of the crime.”

“Yes,” said Daneel, “someone must have been there to place the poison in the liquid.”

“Isn’t it possible that the poisoned liquid might have been prepared earlier in the day? Perhaps much earlier?”

Daneel said quietly, “I had thought of that, Partner Elijah, which is why I used the word ‘apparently’ when I stated that Mrs. Delmarre had no direct connection with the crime. It is within the realm of possibility for her to have been on the scene earlier in the day. It would be well to check her movements.”

“We will do that. We will check whether she was physically present at any time.”

Baley’s lips twitched. He had guessed that in some ways robotic logic must fall short and he was convinced of it now. As the roboticist had said: Logical but not reasonable.

He said, “Let’s get back into the viewing room and get Gruer’s estate back in view.”

The room sparkled with freshness and order. There was no sign at all that less than an hour before a man had collapsed in agony.

Three robots stood, backs against the wall, in the usual robotic attitude of respectful submission.

Baley said, “What news concerning your master?”

The middle robot said, “The doctor is attending him, master.”

“Viewing or seeing?”

“Viewing, master.”

“What does the doctor say? Will your master live?”

“It is not yet certain, master.”

Baley said, “Has the house been searched?”

“Thoroughly, master.”

“Was there any sign of another master beside your own?”

“No, master.”

“Were there any signs of such presence in the near past?”

“Not at all, master.”

“Are the grounds being searched?”

“Yes, master.”

“Any results so far?”

“No, master.”

Baley nodded and said, “I wish to speak to the robot that served at the table this night.”

“It is being held for inspection, master. Its reactions are erratic.”

“Can it speak?”

“Yes, master.”

“Then get it here without delay.”

There was delay and Baley began again. “I said—”

Daneel interrupted smoothly. “There is interradio communication among these Solarian types. The robot you desire is being summoned. If it is slow in coming, it is part of the disturbance that has overtaken it as the result of what has occurred.”

Baley nodded. He might have guessed at interradio. In a world so thoroughly given over to robots some sort of intimate communication among them would be necessary if the system were not to break down. It explained how a dozen robots could follow when one robot had been summoned, but only when needed and not otherwise.

A robot entered. It limped, one leg dragging. Baley wondered why and then shrugged. Even among the primitive robots on Earth reactions to injury of the positronic paths were never obvious to the layman. A disrupted circuit might strike a leg’s functioning, as here, and the fact would be most significant to a roboticist and completely meaningless to anyone else.

Baley said cautiously, “Do you remember a colorless liquid on your master’s table, some of which you poured into a goblet for him?”

The robot said, “Yeth, mathter.” A defect in oral articulation, too!

Baley said, “What was the nature of the liquid?”

“It wath water, mathter.”

“Just water? Nothing else?”

“Jutht water, mathter.”

“Where did you get it?”

“From the rethervoir tap, mathter.”

“Had it been standing in the kitchen before you brought it in?”

“The mathter preferred it not too cold, mathter. It wath a thtanding order that it be poured an hour before mealth.”

How convenient, thought Baley, for anyone who knew that fact. He said, “Have one of the robots connect me with the doctor viewing your master as soon as he is available. And while that is being

done, I want another one to explain how the reservoir tap works. I want to know about the water supply here.”

The doctor was available with little delay. He was the oldest Spacer Baley had ever seen, which meant, Baley thought, that he might be over three hundred years old. The veins stood out on his hands and his close-cropped hair was pure white. He had a habit of tapping his ridged front teeth with a fingernail, making a little clicking noise that Baley found annoying. His name was Altim Thool.

The doctor said, “Fortunately, he threw up a good deal of the dose. Still, he may not survive. It is a tragic event.” He sighed heavily.

“What was the poison, Doctor?” asked Baley.

“I’m afraid I don’t know.” (Click-click-click.)

Baley said, “What? Then how are you treating him?”

“Direct stimulation of the neuromuscular system to prevent paralysis, but except for that I am letting nature take its course.” His face, with its faintly yellow skin, like well-worn leather of superior quality, wore a pleading expression. “We have very little experience with this sort of thing. I don’t recall another case in over two centuries of practice.”

Baley stared at the other with contempt. “You know there are such things as poisons, don’t you?”

“Oh yes.” (Click-click.) “Common knowledge.”

“You have book-film references where you can gain some knowledge.”

“It would take days. There are numerous mineral poisons. We make use of insecticides in our society, and it is not impossible to obtain bacterial toxins. Even with descriptions in the films it would take a long time to gather the equipment and develop the techniques to test for them.”

“If no one on Solaria knows,” said Baley grimly, “I’d suggest you get in touch with one of the other worlds and find out. Meanwhile, you had better test the reservoir tap in Gruer’s mansion for poison. Get there in person, if you have to, and do it.”

Baley was prodding a venerable Spacer roughly, ordering him about like a robot and was quite unconscious of the incongruity of it. Nor did the Spacer make any protest.

Dr. Thool said doubtfully, “How could the reservoir tap be poisoned? I’m sure it couldn’t be.”

“Probably not,” agreed Baley, “but test it anyway to make sure.” The reservoir tap was a dim possibility indeed. The robot’s explanation had shown it to be a typical piece of Solarian self-care. Water might enter it from whatever source and be tailored to suit. Microorganisms were removed and non-living organic matter eliminated. The proper amount of aeration was introduced, as were various ions in just those trace amounts best suited to the body’s needs. It was very unlikely that any poison could survive one or another of the control devices.

Still, if the safety of the reservoir were directly established, then the time element would be clear. There would be the matter of the hour before the meal, when the pitcher of water (exposed to air, thought Baley sourly) was allowed to warm slowly, thanks to Gruer’s idiosyncrasy.

But Dr. Thool, frowning, was saying, “But how would I test the reservoir tap?”

“Jehoshaphat! Take an animal with you. Inject some of the water you take out of the tap into its veins, or have it drink some. Use your head, man. And do the same for what’s left in the pitcher, and if that’s poisoned, as it must be, run some of the tests the reference films describe. Find some simple ones. Do something.”

“Wait, wait. What pitcher?”

“The pitcher in which the water was standing. The pitcher from which the robot poured the poisoned drink.”