"By three or four o'clock on Wednesday morning," Jim echoed, examining the chart once more, and carefully noting the ship's position. "Why, it's Wednesday now, Julian. We've crossed 180°."
"But what day was yesterday?" Martin asked, all trembling.
"Why, yesterday," I answered, "was Wednesday the tenth, my boy; but to-day is Wednesday the tenth also. It comes twice over at this longitude. We've gained a day; that's the long and the short of it. We ought to have known it, my brother and I, who are such old hands at cruising in and out of the islands; but our anxiety and distress made us clean forget it."
"How does that come about?" Martin asked bewildered, his lips white as death.
"Just like this," said I. "Sailing one way, you see, from England, you sail with the sun; and sailing the other way, you sail against it. In one direction you keep gaining time, and in the other you lose it."
"The meridian of 180° is the particular place where the two modes of reckoning reach their climax," I hastened to add. "So, when you get to 180°, sailing west, you lose a day, and Saturday's followed right off by Monday. But sailing east, you gain a day, and have two Sundays running, or whatever else the day may be when you happen to get there. Now, we're going in the right direction for gaining a day; and so, though yesterday was Wednesday the tenth the other side of 180°, to-day's Wednesday the tenth, don't you see, this side of it? And as Tanaki's this side, your people must always have reckoned by the American day, so to speak, while we've reckoned all along by the Australian one. It's this morning those savages threatened to kill your father and mother, and if we make a good run, we shall still perhaps be in time to save them."
As I spoke, the boy's knees trembled under him with excitement. He staggered so that he caught at a rope for support. He was too much in earnest to cry, but the tears stood still in his eyes without falling.
"Oh! I hope to Heaven we'll be in time," he answered. "We may save them! We may save them!"
I went below and turned in once more for a little sleep, for I knew I should be wanted later in the morning; and having fortunately the true sailor's habit in that matter of dozing off whenever occasion occurred, I was soon snoring away again most comfortably on my pillow. At half-past three, Tom Blake came down once more to wake me.
"Land in sight, sir," he said, "on our starboard bow, and this young fellow Martin says he makes it out to be the north point of Tanaki."