It was Saturday evening. Manual work on board had been set aside to be resumed early on Monday morning. Beverley, who was beginning to feel the strain of long hours and hard toil, had turned in early. Villiers, with the small table of his cabin covered with technical books, was deep in _Norrie's Epitome_ and _The Nautical Almanac for_ 1920. "Yacht, ahoy!" Jack heard the hail but did not stir. Calls of that sort were common, considering that there were half a dozen yachts, with hands living on board, lying in the tier out in the stream. "_Titania_, ahoy!" "For goodness sake why didn't you say so before?" exclaimed Villiers to himself. "Where's Tommy? Why didn't he bark, I wonder?" Getting into his pilot-coat, for the night air blew coldly down the river and contrasted forcibly with the warm cabin, Villiers went on deck. "Ahoy, there!" he exclaimed. On the edge of the wharf stood a man with his back to the feeble gleam of a gas-lamp. "Telegram for Harborough, yacht _Titania_," he announced. "Prepaid wire." "Come aboard," said Jack. "Sorry, sir," was the reply. "I'm a stranger to this sort of game. No hand at ladders, I'm not." Considering the awkward means of gaining the _Titania's_ deck, the man's objection was reasonable enough, so Villiers descended the wire-rope ladder, crossed the raft, and ascended the vertical steps. The tide had almost finished on the flood, and there were only a few rungs to scale. "Prepaid, eh?" remarked Villiers. "All right. I have a pencil. Let's go under the gas-lamp." The next instant a multitude of dazzling lights flashed before his eyes, and without a cry he pitched head-long on his face. * * * * * "Jack, old thing!" shouted Beverley, throwing back his blankets and jumping from his cot. "What's the time? Why, it's eight bells! Who's turn is it to light the stove this morning?" Receiving no reply from the adjoining cabin, Bobby laid hold of a sponge, dipped it in the water-jug, and made his way softly to Villiers' berth. He opened the door and looked in. "What's he doing?" he thought in wonderment, for the cot had not been slept in. The lamp was still alight, but on the point of burning itself out. It was an oil-lamp, for the electric-lighting arrangements were not yet in working order. The table was littered with books, two of them open, while a pipe, with a small heap of white ash, lay upon the open page of the _Nautical Almanac_. "I believe he's been swotting all night, the mouldy old book-worm," thought Beverley. "Now he's gone to the bathroom to shove his heated brow in cold water." But the bathroom was empty. A hurried search brought no sign of his chum--nor of the dog. Fearful of his own surmises, Bobby looked over the side. Almost the first thing he noticed was the dead body of Tommy left stranded on the mud by the falling tide, but of Villiers not a trace.