"A thousand thanks," answered Mildmay. "Of course I need not tell you that to interfere in a case of this kind, with no knowledge of the facts, is a somewhat ticklish business. But, all the same, that is not going to stop me. I see, yonder, a British ship flying from a stranger; and with your kind permission I am going to lend her a hand." He raised his glasses to his eyes again. The hull of the leading ship had by this time almost topped the horizon, and it was now possible to see something of her shape. She was a fairly big craft, measuring, according to Mildmay's estimate, about eight thousand tons; and her whole shape and appearance confirmed him in his original conviction that she was one of the X. and Z. Company's boats. She flew no flag at her masthead, it is true; but Mildmay could now see that she had hoisted a blue ensign on her ensign staff. "Under the command of a R.N.R. man," he commented, as he saw this. "All right, old man; there is a friend within a few miles of you, whose proximity you probably don't suspect; and we will see that you don't come to any harm. Now let us have a look at t'other chap." The second craft was still hull-down; but her masts, funnels, tops of her ventilators, and the head of her ensign staff were all visible; and Mildmay noticed that she was showing no colours. This fact rendered the whole affair more puzzling than ever; for there could be no possible doubt that she was chasing the liner, and for a man-o'-war openly and undisguisedly to chase another ship, and not show her colours, was unprecedented, and most certainly not in accordance with any recognised rule of warfare. Meanwhile, the rest of the party had come on deck, and were all intently watching the two ships through their binoculars as they animatedly discussed the puzzling situation. "When do you intend to haul up, `skipper'?" asked Sir Reginald. "Not yet," answered Mildmay. "Perhaps in about ten minutes' time-- unless anything occurs of a character that would make it desirable to do so earlier. I want to see a little more of the game first." "Then there you have it!" exclaimed Lethbridge, as a flash, followed by a puff of brilliant white smoke, issued from the bows of the pursuing ship. A jet of foam leaped up from the surface of the sea, about half a mile astern of the liner, and dissolved like steam in the dazzling sunshine. Then the boom of the gun came floating down to the ears of the watchers. "A four-inch, by the sound of it," remarked Mildmay. "And shotted, too. Clearly, the fellow is in earnest, whoever he may be. Now, what the dickens is the explanation of this enigma? And what is the nationality of the craft?" "Can't you tell by the build of her?" demanded Lethbridge. "I have always understood that you sailors had but to look at a ship to tell her nationality at once; at least that is the impression that one gathers from the general run of sea novels."