"Exactly eight bells--four o'clock," he remarked. "We must drive these little hookers through it for all they are worth, or we shall have the darkness upon us before we sight the ship," and he flung a somewhat anxious glance aloft at the heavy and rather threatening aspect of the sky. For within the last half-hour the sky had thickened somewhat, and ragged patches of scud were sweeping swiftly along overhead, with a dark and lowering bank of clouds behind them to windward, while the breeze had freshened very perceptibly. The sea was increasing, and the boats were already drenching their occupants with the heavy showers of spray that they flung aft, as they met and drove headlong into and through the head-sea. The boats were magnificent little craft, for their size, but Mildmay knew that matters might easily become very awkward indeed for them, even in the short space of an hour or two, out there in the broad Pacific, should it come on to blow at all heavily. Moreover, there was no moon now, and the night promised to be dark. What if they should fail to find the ship! The boats, however, were doing their work splendidly, despite the wind and the sea; and although the tendency of the weather was undoubtedly to grow worse rather than better, the change was so gradual at first as to be scarcely perceptible. But the sunset that night was wild--a sunset of smoky scarlet and fiery orange in the midst of a stormy flare of greenish-purple clouds; and when the sun disappeared the boats still had very nearly half an hour to run before reaching the point at which Mildmay estimated that they ought to shift their helms again to get into the track of the ship. Taking into consideration the retardation of the boats by the adverse influence upon them of the wind and sea, he allowed them an extra ten minutes, and then gave the order to haul up to north-east-by-east, by which time it was pitch dark, starless, and blowing strong, with a very awkward amount of sea running for such small boats to battle with. Fortunately, Mildmay and the professor had with them their diving-dresses and the electric lamps which formed part of their equipment; they thus possessed the means of lighting up the cards of the boat compasses, and so ensuring that they were steering the correct course. "According to my reckoning," said Mildmay, "we ought now to be on or very near the track of the ship, and within about five miles of her, or thereabout. If it were daylight I should expect to see her by this time; as it is we must keep a look-out for her saloon lights. The professor and I have all that we can do to keep the boats running straight, so we shall have to depend upon you other fellows to look out. Don't confine yourselves to looking straight ahead; keep a look-out broad on each bow as well. My calculations are only approximate, you must remember."