"No," said Thissell. "I have merely a favor to ask you."

"I'll oblige if I possibly can," Kershaul replied courteously.

"Give me, or lend me, one of your slaves, for a week or two."

Kershaul played an exclamation of amusement on the . "I hardly like to part with my slaves; they know me and may ways --"

"As soon as I catch Angmark you'll have him back."

"Very well," said Kershaul. He rattled a summons on his , and a slave appeared. "Anthony," sang Kershaul, "you are to go with Ser Thissell and serve him for a short period."

The slave bowed, without pleasure.

Thissell took Anthony to his houseboat, and questioned him at length, noting certain of the responses upon a chart. He then enjoined Anthony to say nothing of what had passed, and consigned him to the care of Toby and Rex. He gave further instructions to move the houseboat away from the dock and allow no one aboard until his return.

He set forth once more along the way to the landing field, and found Rolver at a lunch of spiced fish, shredded bark of the salad tree, and a bowl of native currants. Rolver clapped an order on the , and a slave set a place for Thissell. "And how are the investigations proceeding?"

"I'd hardly like to claim any progress," said Thissell. "I assume that I can count on your help?"

Rolver laughed briefly. "You have my good wishes."

"More concretely," said Thissell, "I'd like to borrow a slave from you. Temporarily."

Rolver paused in his eating. "Whatever for?"

"I'd rather not explain," said Thissell. "But you can be sure that I make no idle request."

Without graciousness Rolver summoned a slave and consigned him to Thissell's service.

On the way back to his houseboat, Thissell stopped at Welibus's office.

Welibus looked up from his work. "Good afternoon, Ser Thissell."

Thissell came directly to the point. "Ser Welibus, will you lend me a slave for a few days?"

Welibus hesitated, then shrugged. "Why not?" He clacked his ; a slave appeared. "Is he satisfactory? Or would you prefer a young female?" He chuckled, rather offensively to Thissell's way of thinking.

"He'll do very well. I'll return him in a few days."

"No hurry." Welibus made an easy gesture and returned to his work.

Thissell continued to his houseboat, where he separately interviewed each of his two new slaves and made notes upon his chart.

Dusk came soft over the Titanic Ocean. Toby and Rex sculled the houseboat away from the dock, out across the silken waters. Thissell sat on the deck listening to the sound of soft voices, the flutter and tinkle of musical instruments. Lights from the floating houseboats glowed yellow and wan watermelon-red. The shore was dark; the Night-men would presently come slinking to paw through refuse and stare jealously across the water.

In nine days the Buenaventura came past Sirene on its regular schedule; Thissell had his orders to return to Polypolis. In nine days, could he locate Haxo Angmark?

Nine days weren't too many, Thissell decided, but they might possibly be enough.

Two days passed, and three and four and five. Every day Thissell went ashore and at least once a day visited Rolver, Welibus and Kershaul.

Each reacted differently to his presence. Rolver was sardonic and irritable; Welibus formal and at least superficially affable; Kershaul mild and suave, but ostentatiously impersonal and detached in his conversation.

Thissell remained equally bland to Rolver's dour jibes, Welibus's jocundity, Kershaul's withdrawal. And every day, returning to his houseboat, he made marks on his chart.

The sixth, the seventh, the eighth days came and passed. Rolver, with rather brutal directness, inquired if Thissell wished to arrange for passage on the Buenaventura. Thissell considered, and said, "Yes, you had better reserve passage for one."

"Back to the world of faces," shuddered Rolver. "Faces! Everywhere pallid, fish-eyed faces. Mouths like pulp, noses knotted and punctured; flat, flabby faces. I don't think I could stand it after living here. Luckily you haven't become a real Sirenese."

"But I won't be going back," said Thissell.

"I thought you wanted me to reserve passage."

"I do. For Haxo Angmark. He'll be returning to Polypolis, in the brig."

"Well, well," said Rolver. "So you've picked him out."

"Of course," said Thissell. "Haven't you?"

Rolver shrugged. "He's either Welibus or Kershaul, that's as close as I can make it. So long as he wears his mask and calls himself either Welibus or Kershaul, it means nothing to me."

"It means a great deal to me," said Thissell. "What time tomorrow does the lighter go up?"

"Eleven twenty-two sharp. If Haxo Angmark's leaving, tell him to be on time."

"He'll be here," said Thissell.

He made his usual call upon Welibus and Kershaul, then returning to his houseboat, put three final marks on his chart.

The evidence was here, plain and convincing. Not absolutely incontrovertible evidence, but enough to warrant a definite move. He checked over his gun. Tomorrow, the day of decision. He could afford no errors.