At ten the relief watch was called. Mr. Armitage came on deck wearing his pilot coat. He made no attempt to check the course or to offer any suggestions. He was placing his crew entirely on their mettle, but from what he saw he had no cause to criticize. Stratton, having "handed over" to Warkworth, went below, where Hepburn had a hot supper ready for those of the crew who had come off duty. "Where's Roche?" he inquired, seeing that the rest of the watch--Woodleigh and Rayburn--were already "tucking in" with avidity. "Yarning with Flemming about something," replied Woodleigh. "I fancy there's trouble in the engine-room." Presently Roche appeared. "Lend me your torch, Peter, old son," he said. "Aren't you grubbing?" asked the Patrol Leader. Roche shook his head. "I'm seeing this thing through first," he replied. "She's not been running well this last hour or two. Too rich a mixture, I think. Flemming and I are going to take the jet out, but before we start I want to see how much oil there is in the main tank." Peter handed Roche his torch. "We'll keep your grub hot," he added as the engineer hurried out of the cabin. In less than a minute Roche returned. "We're in a bad way," he announced. "She's been mopping up the juice like anything. The paraffin tank's nearly empty." "Why, how's that?" asked Stratton. "Punctured float, I'm afraid," replied Roche. "We'll have to stop the motor for half an hour or so." "Right-o," assented the Patrol Leader, pushing away his cup, saucer, and plate. "I'll come and bear a hand. Have you reported to Mr. Armitage?" The Scoutmaster received the news without expressing any suggestion. "Carry on," he remarked. The Sea Scouts accordingly "carried on". They had but one red lamp on board in addition to the port light. Two red masthead lights were required to indicate that the _Olivette_ was not under command. It was the Tenderfoot who solved the problem by suggesting that the white masthead light should be covered with the fold of the Red Ensign. The "not under command" lights were hoisted, and the port and starboard ones extinguished. The ignition to the motor was switched off, and Stratton, Roche, and Flemming proceeded to take down the carburetter, while Woodleigh held the electric torch to enable them to see what they were doing. They worked methodically, placing a piece of canvas under the carburetter to catch any nut that might be accidentally dropped, while all the loose parts were carefully placed in a small tin box. The float was deftly removed. "It feels suspiciously heavy," declared Flemming. "Yes, it's chock full of paraffin or petrol." "Take it into the after-cabin," said Peter. "We'll solder it there. It will be a jolly sight safer away from the engine-room. Get the Tinol box out, Dick." The first part of the operation was the boiling of the float. The hot water would not only cause the confined air to escape and indicate the position of the leak, it would also expel the petrol.