"I think not--unless it is necessary for some purpose that may arise later. Right now I see no need of landing." "There are sure to be Turkish warships there, sir?" "I should think so, surely." "When do you reckon we shall reach there?" "I had planned to enter the harbor about midnight." "Best time for such work, sir." "We'll be aided by a moon tonight--or should be, at least." And it was midnight when the D-16, with her deck barely awash, drew into the harbor of Constantinople, slinking silently along, with every man at his post, seeking out her prey. "Warship dead ahead," called Lord Hastings, and gave the command to stop. "We couldn't want a better place to launch a torpedo," he added. "A miss at this distance is out of the question." The crew stood at attention, and action came swift and fast. "Fire!" came the command at last. A torpedo sped on its way. Immediately the D-16 darted away to a safe place, and then arose to the surface to see the result of its work. A half moon lighted up the scene about them, and Frank and Jack ascended to the bridge. Lord Hastings remained below. Of a sudden a terrible din broke the stillness of the night. Hideous cries went up into the sky. Searchlights broke forth and swept the harbor. Aboard the Turkish warship, the victim of the submarine's torpedo, confusion reigned. Officers tried in vain to restore some semblance of order among the crew until they could ascertain the extent of the damage done. It was impossible. Never the coolest sailors in the world, the Turks lost whatever courage they may have possessed and a panic ensued aboard the wounded warship, which soon spread to other vessels in the harbor. There seemed to be no doubt in the mind of any as to the cause of the explosion. "We'll go down and try another one," said Jack calmly. They descended below, and a few moments later the D-16 was moving toward another victim. This ship and then a third were torpedoed with unerring aim, and the panic which followed above was terrible to behold. In the city itself word of the disaster spread, and the Sultan and his cabinet, believing that the fall of the capital was imminent, hurriedly got together what papers of state they could lay their hands upon, and dashed in automobiles from the city. "Well," said Jack to Lord Hastings, "I guess we might as well call it a good night's work and let it go at that." "I am of the same opinion," replied his commander. "We must have created a terrible furore." "There is not much question about that," said Frank with satisfaction. "I would like to go ashore and see what is going on." "I wouldn't object to that either," said Jack. "It's impossible," declared Lord Hastings. "You would surely be captured." "I don't think so," said Jack. "In this confusion a boat could easily be launched and no one would be the wiser. Then, if you remained right here, we could return without trouble."