"I'm sure," said Rocky primly, "it would be most interesting. But I hate to trouble you--" "No trouble, Puffessor. No trouble a-tall. 'Course my throat is gettin' a mite dry-like from talkin' so much. I might could use a sip o' water ... or mebbe a drap o' likker to sorta loosen my tongue--" Rocky dug deep, and a coin passed between him and his informant. "Please allow me, Gunner. And many thanks. We'll have another little chat soon. I'm afraid I must be running along now, though." Followed by his two companions, he climbed from the pill-box embrasure in which he had been interviewing the not-too-reliable old Patrolman. * * * * * Two days had passed since "Dr. Roswell" and his aide had taken up residence in the Base. In that time, Rocky had wandered much, talked much, and learned much. Slowly he was beginning to gather that accumulation of facts which, he hoped and believed, would ultimately bring the weight of the Law to bear on Factor Humboldt Grossman. Exactly what Grossman's racket was, he _still_ didn't know. But from various and sundry sources he had heard tales of the fat man's greed and cunning, his autocratic domination over a number of the lower-class Titanians. In his own small way, and to those rebels he had gathered about him, Humboldt Grossman was emperor of New Boston. It remained to be proven whether or not he could extend his control to embrace the whole of the satellite. Emerging from the sunken gunnery pit, the trio found themselves upon one of the metal highways which criss-crossed the little world. To their left lay the squat, grim rows of structures which comprised Fort Beausejour, the Solar Space Patrol base on Titan. Barracks, administration and ordnance headquarters, messhalls, dumps and depots mingled in gray heterogeneity behind a strong defense-in-depth calculated to withstand months of siege or any known form of military attack. To their right, several miles distant at the far end of the highway, lay the city of New Boston. It was a strange city, a curious commingling of ancient and modern, savage and cultured, alien and civilized. It boasted two tremendous skyscrapers of ultramodern design constructed by Earth colonists, but about and around these, clustered like mud-daubers' nests, clung rows upon rows, thousands upon countless thousands, of tiny, dingy, one-story hovels ... the dwellings of the natives. It was into this city Rocky Russell's investigations now led him. He glanced at his wrist chronometer. "Bless my soul! Very nearly time for my appointment with Factor Grossman. You are sure we can use a roller, Miss Graham?" "Positive," answered the girl cheerfully. "I asked Daddy yesterday. You wait here; I'll get it and come back." She moved away, giving the two S.I.D. men their first moment of privacy in hours. Bud Mulligan sighed and fumbled for a cigarette.