north; its western border was Third Avenue, its eastern, the East River. From here, the UN ruled Earth. There were no walls or fences around it; only by looking at street signs could anyone tell that they had crossed an international border. Crossing Third Avenue from west to east, one found that 45th Street had suddenly become Deutschland Strasse; 40th Street became Rue de France; 47th was the Via Italiano. 43rd Street's sign was painted in Cyrillic characters, but beneath it, in English, were the words "Avenue of Mother Russia." Third Avenue was technically One World Drive. Second Avenue was labelled as Planetary Peace Drive, and First was United Nations Drive. But New Yorkers are, and always have been, diehards. Just as The Avenue of the Americas had forever remained Sixth Avenue, no matter what the maps called it, so had the other streets retained their old names in conversation. Even the International Post Office, after years of wrangling, had given up, and letters addressed to Supreme Headquarters, United Nations Police, 45th Street at Second Avenue, were delivered without comment, even though the IPO still firmly held that they were technically misaddressed. And, privately, even the IPO officials admitted that the numbers were easier to say and remember than the polyglot street names that had been tagged on by the General Assembly. So when David Houston signalled a taxi at Grand Central Station and said, "Forty-fifth and Second," the driver simply set his automatic controls, leaned back in his seat, and said, "Goin' to see the cops, huh?" When no answer was forthcoming, the driver turned around and took a good look at his passenger. "Maybe you're a UN cop yourself, huh?" Houston shook his head. "Nope. Some kids have been scribbling dirty words on my sidewalk, and I'm going to report it to the authorities." The driver turned back around and looked ahead again. "Jeez! That's serious. Hadn't you better take it up with the Secretary General? I wouldn't be satisfied with no underlings in a case like that." "I'm thinking of taking it up with the Atomic Energy Control Board," Houston told him. "I think those kids are using radioactive chalk." "That's one way for 'em to get blue jeans," said the driver cryptically. There was