The Montauk continued to gain on her pursuer until the sun set, when Captain Truck began once more to cast about him for the chances of the night. He knew that the ship was running into the mouth of the Bay of Biscay, or at least was fast approaching it, and he bethought him of the means of getting to the westward. The night promised to be anything but dark, for though a good many wild-looking clouds were by this time scudding athwart the heavens, the moon diffused a sort of twilight gleam in the air. Waiting patiently, however, until the middle-watch was again called, he reduced, sail, and hauled the ship off to a south-west course, hoping by this slight change insensibly to gain an offing before the Foam was aware of it; a scheme that he thought more likely to be successful, as by dint of sheer driving throughout the day, he had actually caused the courses of that vessel to dip before the night shut in. Even the most vigilant become weary of watching, and Captain Truck was unpleasantly disturbed next morning by an alarm that the Foam was just out of gun-shot, coming up with them fast. On gaining the deck, he found the fact indisputable. Favoured by the change in the course, the cruiser had been gradually gaining on the Montauk ever since the first watch was relieved, and had indeed lessened the distance between the respective ships by two-thirds. No remedy remained but to try the old expedient of getting the wind over the taffrail once more, and of showing all the canvas that could be spread. As like causes are known to produce like effects, the expedient brought about the old results. The packet had the best of it, and the sloop-of-war slowly fell astern. Mr. Truck now declared he would make a "regular business of it," and accordingly he drove his ship in that direction throughout the day, the following night, and until near noon of the day which succeeded, varying his course slightly to suit the wind, which he studiously kept so near aft as to allow the studding-sails to draw on both sides. At meridian, on the fourth day out, the captain got a good observation, and ascertained that the ship was in the latitude of Oporto, with an offing of less than a degree. At this time the top-gallant sails of the Foam might be discovered from the deck, resembling a boat clinging to the watery horizon. As he had fully made up his mind to run into port in preference to being overhauled, the master had kept so near the land, with an intention of profiting by his position, in the event of any change favouring his pursuers; but he now believed that at sunset he should be safe in finally shaping his course for America.