"If you, the Sea Scout, who are signalling, are one of the survivors, come aboard us immediately. Let your shipmates be taken into Haddisport."
Mark was not altogether surprised when he saw that the midshipman in charge of the pinnace was his own brother Rodney. They shook hands as he stepped into the stern sheets, but preserved a discreet silence before the men.
Saluting the quarter-deck as they boarded the Atreus, Mark found himself face to face with a group of officers. He advanced towards the commander.
"If you will lend me a chart, sir," he began, "I will show you exactly the way the mine-layer went. She has been sowing mines all along her track."
A chart was at once opened on top of the skylight, and with a pencil Mark traced as nearly as he could the Minna von Barnhelm's course, from the time when he first saw her until she disappeared.
"It was just here where she began laying mines," he explained, indicating the spot, "about three miles to the east of where we are now. If you keep well to the westward, you will escape them, sir. But I can't say which way she steered after we lost sight of her."
"Of course not," nodded the commander. "You have done very well as it is. I'm tremendously obliged to you for the information."
He turned to his officers and gave orders for the squadron to proceed at full speed in pursuit, handing the navigation officer the marked chart.
"There's another thing," resumed Mark, fumbling in his pocket-book, and producing the strip of paper taken from Darby Catchpole's pigeon. He explained how he had come by it, adding: "It seems to be written in German shorthand. Perhaps you will take charge of it, sir."
"Excellent," smiled the commander. "You have your wits about you, my lad. You have acted with commendable good sense and promptitude. This matter of the mine-field is most important. What is your name?"