"Experimental?" Merrit repeated.

"Affirmative, Commander."

"How experimental?" he prompted tautly.

"I am a prototype." The Bolo sounded calmer than ever beside the tension in his own voice. "As part of the Enhanced Combat Capabilities Program, my Command Center and Personality Integration psychodynamics were fitted with a secondary decision cortex with experimental interfaces and increased heuristic capacity to augment autonomous and discretionary functions."

"A brain box," Merrit whispered. "Dear God, that must be it. The first brain box ever fitted to a Bolo!" He went to his knees and rested one hand almost reverently on the massively armored deck.

"Excuse me, Commander, but the meaning of your last comment is unclear."

"What?" Merrit shook himself, then raised his head and smiled into the nearest optical head. "Sorry, Nike, but I had no idea I'd find this. You're the 'missing link.'"

"I fear your meaning continues to elude me, Commander," the Bolo said a bit reproachfully, and Merrit grinned.

"Sorry," he said again, and seated himself on the bracket of a turret-mounted whip antenna. "You see, Nike, before you came along-for that matter, for something like thirty years after you came along, now that I think about it-Bolos were self-aware, but their full autonomous capabilities were available to them only in Battle Mode. They were... circumscribed and restricted. Are you with me so far?"

"Yes, Commander."

"Of course you are!" Merrit chuckled and patted the leviathan's armored flank. "But that's because you were the next step, Nike. We knew the first experimental work had been done here in the Ursula Sector just before the Quern Wars, but the Quern got through to Ursula during the First War. They shot up Bolo Central so badly that most of the original research and hardware was destroyed, and then the pressure they put on us deferred the whole program for over thirty years, until after the Third Quern War. We needed more Bolos as fast as we could get them, so the official Mark XXIIIs were simply up-gunned and up-armored Mark XXIIs to simplify series production. But you weren't, were you? God! I wonder how your programming differs from what they finally mounted in the Mark XXIV?"