Immediately, as the contragravity field dropped below the specific gravity of the ship, she began submerging. I got up into the conning tower in time to see the water of the boat pool come up over the armor-glass windows and the outside lights come on. For a few minutes, the _Javelin_ swung slowly and moved forward, feeling her way with fingers of radar out of the pool and down the channel behind the breakwater and under the overhang of the city roof. Then the water line went slowly down across the windows as she surfaced. A moment later she was on full contragravity, and the ship which had been a submarine was now an aircraft. Murell, who was accustomed to the relatively drab sunsets of Terra, simply couldn't take his eyes from the spectacle that covered the whole western half of the sky--high clouds streaming away from the daylight zone to the west and lighted from below by the sun. There were more clouds coming in at a lower level from the east. By the time the _Javelin_ returned to Port Sandor, it would be full dark and rain, which would soon turn to snow, would be falling. Then we'd be in for it again for another thousand hours. Ramón Llewellyn was saying to Joe Kivelson: "We're one man short; Devis, Abdullah's helper. Hospital." "Get hurt in the fight, last night? He was right with us till we got out to the elevators, and then I missed him." "No. He made it back to the ship about the same time we did, and he was all right then. Didn't even have a scratch. Strained his back at work, this morning, trying to lift a power-unit cartridge by hand." I could believe that. Those things weighed a couple of hundred pounds. Joe Kivelson swore. "What's he think this is, the First Century Pre-Atomic? Aren't there any lifters on the ship?" Llewellyn shrugged. "Probably didn't want to bother taking a couple of steps to get one. The doctor told him to take treatment and observation for a day or so." "That's Al Devis?" I asked. "What hospital?" Al Devis's strained back would be good for a two-line item; he'd feel hurt if we didn't mention it. "Co-op hospital." That was all right. They always sent in their patient lists to the _Times_. Tom was griping because he'd have to do Devis's work and his own. "You know anything about engines, Walt?" he asked me. "I know they generate a magnetic current and convert rotary magnetic current into one-directional repulsion fields, and violate the daylights out of all the old Newtonian laws of motion and attraction," I said. "I read that in a book. That was as far as I got. The math got a little complicated after that, and I started reading another book." "You'd be a big help. Think you could hit anything with a 50-mm?" Tom asked. "I know you're pretty sharp with a pistol or a chopper, but a cannon's different." "I could try. If you want to heave over an empty packing case or something, I could waste a few rounds seeing if I could come anywhere close to it."