No incident marred the peaceful progress of the D-16 as she made her way through the sunny waters of the Mediterranean. The weather was beautiful and Lord Hastings, Frank and Jack spent many pleasant hours upon the little bridge. "How long before we shall reach the entrance to the Dardanelles?" asked Frank during one of these siestas. "At the rate we are going," was the reply, "we should be there tomorrow morning. Of course, we might even do better than that, but I am in no particular hurry. There will not be much action before daylight." "I suppose by this time," said Frank, "that progress in reducing the Turkish fortifications is swifter than before." "It's hard to say," was the reply. "The outer forts are, of course, not so strong as the inner fortifications. As you know, having been there, the strait is very narrow, less than a mile in some places, and it is absolutely impossible for warships to force their way through without first destroying all guns on either side." "But you remember our prisoner told us the _Queen Elizabeth_ was wreaking great havoc with these. What do you know of her, sir?" "Not as much as I should. She is the newest of Great Britain's dreadnoughts; and, without the shadow of a doubt, the most powerful sea-fighter afloat today. She carries the heaviest guns and outranges anything afloat. Shore batteries, powerful as they may be, are no match for her, for she can stand off at a distance of twenty miles and pound them with perfect safety to herself." "She must indeed be a terrible engine of destruction," said Frank. "She is," replied Lord Hastings calmly, "and eventually, mark me, she, and ships of her class, will be the means of bringing the Germans to terms, land victories of the most gigantic scale notwithstanding." "Well, the sooner the better," said Frank. "I agree with you," declared Jack. "And I, too," remarked Lord Hastings. It was just after daylight on the following morning that Frank, who was on the bridge, made out in the distance huge clouds of smoke and heard the faint sounds of booming guns. "They are at it again," he told himself. He went below and aroused Jack and Lord Hastings. They were soon dressed and joined Frank on the bridge. Every few seconds, above the sounds of the distant guns, one roared louder than the rest. "The _Queen Elizabeth_," Lord Hastings explained. "Her voice is one that already must have carried terror to the heart of Constantinople and her people." The speed of the submarine was increased, for Lord Hastings wished to arrive upon the scene as soon as possible. Gradually the forms of the huge ships of the allied fleet could be distinguished. "Eighteen, nineteen, twenty," counted Frank. "I thought there were more than that. Where are the others?"