The air hissed and whined along the pipes, and the eardrums of those aboard tingled to the rising pressure from overloaded relief valves. For five minutes the hissing and roaring continued, then at a shouted order the noise stopped. The First Lieutenant looked back from the motionless gauge to the Captain. "Shall we put more on A, sir? Fifty pounds won't have moved any out at this depth...." "No--don't put any more on, I've got One and Two pretty near out and the fifty will blow A as she rises. Then I'm going to fill One and Two again and catch the trim before we break surface. She's stuck in the mud, that's all, and we'll have to pull her out. Stand by the motors, aft there!" The passengers were fidgeting slightly, and the Commander, noting the fidgeting, looked up and spoke, laughing, to the youthful Captain--_apropos_ of absolutely nothing at all. The Captain laughed back (for publication and as a guarantee of good faith) and turned to the motor-room voice-pipe: "Slow ahead Port--half ahead Starboard"--a pause filled by a dry humming from right aft where the big motors purred. "Stop both--slow ahead Starboard--half astern Port"--another droning pause, and then--"Stop Starboard--half astern Starboard." The boat quivered, then with a lurch she pulled free and her bows rose sharply. "Stop both--half ahead both--flood One and Two--flood A--_Dammit_--hard-a-dive, coxswain." The angle increased fast, faster than the forward tanks could fill, and the boat rushed upwards with chests, men, and other loose impediments sliding and slipping aft. At eighty feet she began to level slightly, but the angle could not be taken off her in time,--the destroyer men had a vision of a grey conning-tower foaming ahead for a few seconds, surmounted by fifteen feet of silver periscope, before, to the drive of her powerful screws, the boat dipped again till only the tops of the hooded lenses showed as she settled at her diving depth. "_Rotten_," observed the Captain gloomily to the First Lieutenant. "I mustn't break surface like that when we get to the Bight, or we all go West one-time,--I think that'll do for the dive, though. She'll be tight as a drum when the firm's had another day or two at her. We'll do the helm and speed trials now and then go in. Hands by the blows! _Surface!_" III The Submarine Flotillas began to move to their war bases on the 29th July. By the 4th August they were ready to begin their work. The VIII Flotilla ("D" and "E" boats) were at Harwich, a port which throughout the War has remained the chief Heligoland Bight Patrol base. The "C" boats were spread all up the East Coast, with a Channel guard at Dover and a large number of them at Leith.