"Cap'n, you gotta use a special kinda crawl to get through these here ducts," Thomas said. "You grip your hands together out in front of ya, and then bend your elbows. When your elbows jam against the side of the duct, you pull forward." I tried it; it was slow, but it worked. "Cap'n," Thomas said behind me. "We got about seven minutes now to get up there. I set the control on the converter to start up in ten minutes. I think we can make it O.K., and ain't nobody else comin' this way with the converter goin'. I locked the control panel so they can't shut her down." That news spurred me on. With the converter in operation, the first step in the cycle was the evacuation of the ducts to a near-perfect vacuum. When that happened, we would die instantly with ruptured lungs; then our dead bodies would be sucked into the chamber and broken down into useful raw materials. I hurried. I tried to orient myself. The duct paralleled the corridor. It would continue in that direction for about fifteen feet, and would then turn upward, since the Bridge was some fifteen feet above this level. I hitched along, and felt the duct begin to trend upward. "You'll have to get on your back here, Cap'n," Thomas said. "She widens out on the turn." I managed to twist over. Thomas was helping me by pushing at my feet. As I reached a near-vertical position, I felt a metal rod under my hand. That was a relief; I had been expecting to have to go up the last stretch the way a mountain climber does a rock chimney, back against one wall and feet against the other. I hauled at the rod, and found another with my other hand. Below, Thomas boosted me. I groped up and got another, then another. The remaining slight slant of the duct helped. Finally my feet were on the rods. I clung, panting. The heat in the duct was terrific. Then I went on up. That was some shot Kramer had given me. * * * * * Above I could see the end of the duct faintly in the light coming up through the open chamber door from the utility room. I remembered the location of the disposal slot on the Bridge now; it had been installed in the small apartment containing a bunk and a tiny galley for the use of the Duty Officer during long watches on the Bridge. I reached the top of the duct and pushed against the slot cover. It swung out easily. I could see the end of the chart table, and beyond, the dead radar screen. I reached through and heaved myself partly out. I nearly fainted at the stab from my ribs as my weight went on my chest. My head sang. The light from below suddenly went out. I heard a muffled clank; then a hum began, echoing up the duct. "She's closed and started cyclin' the air out, Cap'n," Thomas said calmly. "We got about half a minute."