Mark returned on deck, wondering what had happened, and was in time to watch the shattered Atreus taking her final plunge—the third ship which he had seen sent to the bottom of the North Sea on that memorable day!

Captain Damant stood near him, also watching.

"I should not have regretted it so much if she had been sunk in fair fight," the captain was saying to one of the officers. "This wholesale mine-laying, however, is something unexampled, and contrary to all international law. It is clear, too, that the enemy must have begun the work days before the declaration of war."

Mark saluted him.

"You wished to see me, sir," he reminded him.

"Yes," the captain nodded; "I wanted to know if the Minna von Barnhelm was the only suspicious-looking craft you saw this morning. But it is now obvious that she was not alone. I don't suppose," he added, "that you quite realise how important it was that you should give such prompt information."

"We didn't save the Atreus, sir," Mark regretted.

"That is true," acknowledged Captain Damant, "because, as a matter of fact, we altered our course, and ran into another mine-field. The important thing is that our wireless message was picked up by a squadron of our Dreadnoughts off the Dogger Bank. They were steaming towards the danger. What do you suppose would have been the result if they, as well as we, had run foul of those German mines? It is thanks to you that the Navy has been saved an even greater disaster than the loss of the Atreus. You may be sure I will see that your good services are recognised."

CHAPTER V.

UNDER THE SYCAMORE.