The Gripping Hand by Larry Niven, Jerry Pournelle

indicated three places near the front of the bus. "Always like to have Navy people with me. I put in nearly forty years. Retired as coxs'n about twenty years ago. I'd have stayed in, but my wife talked me out of it. Civilian life's no good, you know. Nothing to do. Nothing important. Well, I don't mean that the way it sounds."
     
     

    Ruth smiled. "We understand."
     
     

    "Thank you, ma'am. I don't usually talk so much about myself. Sure glad to see Navy people. You Navy, Sir Kevin?"
     
     

    "Reserve. Sailing Master. I went inactive about the same time you retired."
     
     

    Kevin and Ruth took their seats and settled back. Riley produced a hip flask. "Little nip?"
     
     

    "Thank you, no," Kevin said.
     
     

    "You're thinking it's a bit early. Guess it is, even for Sparta, but with the short days we tend to do things a little different here."
     
     

    "Well, why not?" Kevin reached for the flask. "Good stuff. Irish?"
     
     

    "What they call Irish most places. We just call it whiskey. Better strap in."
     
     

    The sky was as crowded as the sea. The bus rose through a swarm of light planes and heavy cargo craft and other airfoil-contoured buses, curved wide away from an empty area a minute before some kind of spacecraft came whistling through it, and went east toward the mountains. It followed the tiers of houses and estates up into the clouds. They broke through cloud cover to see that the black mountaintops went up high above them.
     
     

    "That's pretty," Ruth said. "What do you call those mountains?"
     
     

    "Drakenbergs," Riley said. "Run down most of the length of the Serpens. Serpens is the continent."
     
     

    "Barren up here," Renner said.
     
     

    The Serpens had a sharp-curled spine, black mountain flanks bare of life. Sparta hadn't developed foliage to handle that soil, and it held too much heavy metal for most earthly plants. The tour director told them that and more as they flew along the spine of the continent.
     
     

    The bus dropped back below the tablecloth of clouds and followed the curve of the mountains to where they dipped into the ocean, dropped to half a kilometer altitude, and headed south across the harbor.
     
     

    "That's Old Sparta to the left," Riley said. "Parts date back to CoDominium days. See that green patch with tall buildings around it? That's the Palace area."
     
     

    "Will we go closer?" Ruth asked.
     
     

    " 'Fraid not. There are Palace tours, though."
     
     

    Boats of every size moved randomly across the calm water. They continued south. The calm water of the tremendous harbor changed from green to blue, sharply. The sea bottom was visible, still shallow; the boats were fewer, and larger.
     
     

    "It doesn't show," Ruth said.
     
     

    "Yeah." Renner had guessed what she meant. "They rule a thousand worlds from here, but . . . It's like the zoo on Mote Prime. Sure it's a different world, sure there's nothing like it anywhere in the universe, but you get used to that when you travel enough. You expect major differences. But it's not fair, Ruth. We look for worlds like Earth because that's where we can live."
     
     

    Riley was staring. Other heads had turned from windows. Zoo on Mote Prime?
     
     

    "Defenses," Ruth said. " There's a difference. Sparta must be the most heavily defended world of all."
     
     

    "Yeah. And all that means is, there are places the bus won't go. And questions Mr. Riley won't answer."
     
     

    Riley said, "Well, of course."
     
     

    Ruth was smiling. "Don't test that, all right? I know you. We're on holiday."
     
     

    "Okay."
     
     

    "I don't know anything about Sparta's defenses anyway," Riley said uncomfortably. "Mr. Renner? You were on the Mote expedition?"
     
     

    "Yup. Riley, I didn't keep any secrets, and it's all been declassified. You can get my testimony under What I Did on My Summer Vacation , by Kevin Renner. Published by Athenaeum in 3021. I get a royalty."
     
     

    There was a storm to the east. The bus