"Now," said the Submarine Commander as the pointed bows swung round for the open sea, "we'll get away out of it. Must keep on the surface for a while--too many short-tempered little patrol boats close in to let us cruise with only a periscope showing." He waved his hand in the direction of countless smudges of smoke ringing the clear horizon. "But once we're clear of those we'll dive and hide somewhere for a while. Give old man Gedge something to scratch his head about, lookin' for us. Then we'll play round and test the apparatus.... You'll be able to observe the compass all the time, and I'll give you the distances. There's a young flood making ..." For the space of a couple of hours the boat slid swiftly through the waves and successive cordons of patrols passed them onwards with flickering signals. The men onboard a line of rusty drifters leaned over the sides of their plunging craft and waved as the jaws of their baleful traps opened to let them pass through. Above their heads a gull circled inquisitively, shrilling the high, thin Song of the Seventh Sea: astern the peaks of Ultima Thule faded like opals into the blue. A little cluster of rocky islands rose at length out of the sea ahead; the Submarine Commander took a swift bearing and rolled up the chart. "That'll do," he said; "now we'll dive. There's a shoal patch hereabouts, and we'll sit on the bottom and have lunch while old man Gedge starts looking for us. After lunch we'll let him get near and try a bit of daylight stalking." He glanced at the sun overhead. "Bit early, yet awhile," he added. One by one, led by Sir William, they descended the steel-runged ladder into the electric-lit depths of the Submarine. A hatch closed with a muffled clang: a few curt orders were followed by a succession of gurgles like those of the tide flooding through a cavern; the Commanding Officer moved from the eyepiece of the periscope, and gravely contemplated a needle creeping slowly round the face of a large dial. A Petty Officer, with an expression emotionless as that of a traveller in a railway tunnel, sat by the dial manipulating a brass wheel; a few feet away sat a Leading Seaman similarly employed. The eyes of both men were fixed on the hesitating needle as it shivered round. Finally the needle wavered, crept on another inch and paused, trembling. The Lieutenant-Commander glanced fore and aft, stripped off a pair of soiled gauntlets and made a low-voiced observation. The two men, as if released from a spell, turned away from their dials. "There we are," said the Captain cheerfully, "sitting snug on a nice sandy bottom in ten fathoms of water. What's for lunch?" He led the way forward to a folding table between the polished mahogany bunks. "Fried chops, ain't it?" he enquired, sniffing.