Cliff sat slumped down in his seat, his head tilted upon one shoulder. He had not moved nor made a sound, and his limp silence began to worry Johnny. What if he had struck too hard, had killed the man? A little tremor went over him, a prickling of the scalp. Killing Cliff had no part in his plans, would be too horrid a mischance. He wished now that he had left him alone, had let him bluster and threaten. Perhaps Cliff would not have had presence of mind enough to do what Johnny had feared he would do when he saw capture was inevitable: drop overboard what papers he carried that would incriminate him with the United States Federal officers. With empty pockets Cliff would be as free of suspicion as Johnny himself--a mere passenger in a plane that had flown too far south. He would then be fairly safe in assuming that Johnny would never dare to cross the line with him under the eye of those who watched from the sky. It had been the fear of that ruse that had brought Johnny to the point of violence to Cliff's person, but he was sorry now that he had not risked taking that chance. Flying has its inconveniences, after all, for Johnny could not stop to investigate the injury he had done to Cliff. He would have to go on, now that he was started, but the thought that he might be flying with a dead man chilled what enthusiasm he had felt for the adventure. On over the ocean he flew until he had passed the three-mile limit which he hazily believed would bar the planes of the government unless they had express orders to follow him out. Looking back, he saw that his hunters seemed content to wheel watchfully along the shore line, and presently he banked around and flew north. From the Mexican line to San Diego is not far--a matter of twenty miles or so. Across the mouth of San Diego bay, on the inner shore of which sits the town, North Island stretches itself like a huge alligator lying with its back above water; a long, low, sandy expanse of barrenness that leaves only a narrow inlet between its westernmost tip and the long rocky finger of Point Loma. Time was when North Island was given over to the gulls and long-billed pelicans, and San Diego valued it chiefly as a natural bulkhead that made the bay a placid harbor where the great combing rollers could not ride. But other birds came; great, roaring, man-made birds, that rose whirring from its barrenness and startled the gulls until they grew accustomed to the sight and sound of them. Low houses grew in orderly rows. More of the giant birds came. Nowadays the people of San Diego, looking out across the bay, will sometimes look again to make sure whether the sailing object they see is an airplane or only a gull. In time the gull will flap its wings; the airplane never does. All through the day the air is filled with them--gulls and airplanes sharing amicably the island and the air above it.