"True," Holati said, "but the report the U-League got didn't happen to be the one Professor Mantelish helped make up. We'll go into that later. The plasmoid the professor was experimenting with was the 112-113 unit."

He shifted his gaze to Mantelish. "Still want me to tell it?"

"Yes, yes!" Mantelish said impatiently. "You will oversimplify grossly, of course, but it should do for the moment. At a more leisurely time I shall be glad to give Trigger an accurate description of the processes."

Trigger smiled at him. "Thank you, Professor!" She took her second sip of the Puya. Not bad.

"Well, Mantelish was dosing this plasmoid with mild electrical stimulations," Holati went on. "He noticed suddenly that as he did it other plasmoids in that section of Harvest Moon were indicating signs of activity. So he called in Doctor Fayle and Doctor Azol."

The three scientists discovered quickly that stimulation of the 112 part of the unit was in fact producing random patterns of plasmoid motion throughout the entire base, while an electrical prod at 113 brought everything to an abrupt stop again. After a few hours of this, 112 suddenly extruded a section of its material, which detached itself and moved off slowly under its own power through half the station, trailed with great excitement by Mantelish and Azol. It stopped at a point where another plasmoid had been removed for laboratory investigations, climbed up and settled down in the place left vacant by its predecessor. It then reshaped itself into a copy of the predecessor, and remained where it was. Obviously a replacement.

There was dignified scientific jubilation among the three. This was precisely the kind of information the U-League—and everybody else—had been hoping to obtain. 112-113 tentatively could be assumed to be a kind of monitor of the station's activities. It could be induced to go into action and to activate the other plasmoids. With further observation and refinement of method, its action undoubtedly could be shifted from the random to the purposeful. Finally, and most importantly, it had shown itself capable of producing a different form of plasmoid life to fulfill a specific requirement.

In essence, the riddles presented by the Old Galactic Station appeared to be solved.

The three made up their secret report to the U-League. Included was a recommendation to authorize distribution of ten per cent of the less significant plasmoids to various experimental centers in the Hub—the big and important centers which had been bringing heavy political pressure to bear on the Federation to let them in on the investigation. That should keep them occupied, while the U-League concluded the really important work.

"Next day," said Holati, "Doctor Gess Fayle presented Mantelish with a transmitted message from U-League Headquarters. It contained instructions to have Fayle mount the 112-113 unit immediately in one of the League ships at Harvest Moon and bring it quietly to Maccadon."

Mantelish frowned. "The message was faked!" he boomed.

"Not only that," said Holati. "The actual report Doctor Fayle had transmitted the day before to the League was revised to the extent that it omitted any reference to 112-113." He glanced thoughtfully at Mantelish. "As a matter of fact, it was almost a month and a half before League Headquarters became aware of the importance of the unit."

The professor snorted. "Azol," he explained to Trigger, "had become a victim of his scientific zeal. And I—"

"Doctor Azol," said the Commissioner, "as you may remember, had his little mishap with the plasmoid just two days after Fayle departed."

"And I," Mantelish went on, "was involved in other urgent research. How was I to know what that villain Fayle had been up to? A vice president of the University League!"

"Well," Trigger said, "what had Doctor Fayle been up to?"

"We don't know yet," Holati told her. "Obviously he had something in mind with the faked order and the alteration of the report. But the only thing we can say definitely is that he disappeared on the League ship he had requisitioned, along with its personnel and the 112-113 plasmoid, and hasn't shown up again.

"And that plasmoid unit now appears to have been almost certainly the key unit of the entire Old Galactic Station—the unit that kept everything running along automatically there for thirty thousand years."

He glanced at Quillan. "Someone at the door. We'll hold it while you see what they want."