The Hon. Derek came alongside in one of the steamboats belonging to the parent ship. Smartly returning the salutes of his colleagues, he stepped on board, followed by his coxswain, who bore under his arm a bundle of charts and a large blue envelope bound with red tape.

Lieutenant-Commander Stockdale was in his early thirties, a slimly-built man of medium height and of engaging manners. He had gained his present rank through sheer merit and whole-hearted devotion to the branch of the service in which he specialized. He had unlimited influence behind him; he could easily have secured a "warm billet" on one of the royal yachts, but he had steadfastly set his face against favouritism. Notwithstanding his exalted birth, he was in every sense of the word an officer and a gentleman. A firm disciplinarian, he was ever ready to consider a grievance on the part of his crew. Provided a man was keen and reliable, he could rely upon the skipper's impartiality, but woe betide the luckless individual who attempted to "get to windward" of the Hon. Derek.

It was noon before the signal was received for R19 to proceed. Meanwhile a dozen odd jobs had kept Fordyce busily engaged, and almost before he was aware of the fact the submarine, running awash at ten knots, had passed the "gate" in the boom thrown across the harbour's mouth. Then, increasing speed to eighteen, R19 shaped a course N.N.E., across the mine-infested North Sea.

At eight bells (midnight) the Sub, relieved of duty, went below and prepared to turn in. Switching on an electric light in his diminutive cabin, he gave an exclamation of surprise, for, perched at the foot of his bunk, with a wistful look in her brown eyes, was his Irish terrier—the too faithful Flirt.

CHAPTER V

The Stowaway

Lieutenant-Commander the Hon. Derek Stockdale stooped and patted the dog's head. Flirt, instinctively realizing that she was being caressed by a friend, wagged a stumpy tail and licked the skipper's tanned hand.

It was on the morning following R19's departure and Noel Fordyce's discovery. The submarine was still running awash. North, south, east, and west the horizon was unbroken. Sea and sky met in a sharp, well-defined line. Save for R19, the broad expanse of the North Sea appeared to be deserted, although none could tell what dangers lurked beneath the surface of the dull-green water.

The skipper was taking a stroll on deck when Noel appeared with the four-footed Stowaway. Lieutenant Macquare was on duty on the navigating-platform. For'ard of the conning-tower half a dozen bluejackets, clad in fearnought suits, evinced a lively interest in the proceedings.