The shadow of the stick was nothing but the needle of a dial. The moment had come, and Cyrus Harding knelt on the sand, and with little wooden pegs, which he stuck into the sand, he began to mark the successive diminutions of the stick's shadow. His companions, bending over him, watched the operation with extreme interest. The reporter held his chronometer in his hand, ready to tell the hour which it marked when the shadow would be at its shortest. Moreover, as Cyrus Harding was working on the 16th of April, the day on which the true and the average time are identical, the hour given by Gideon Spilett would be the true hour then at Washington, which would simplify the calculation. Meanwhile as the sun slowly advanced, the shadow slowly diminished, and when it appeared to Cyrus Harding that it was beginning to increase, he asked, "What o'clock is it?"
"One minute past five," replied Gideon Spilett directly. They had now only to calculate the operation. Nothing could be easier. It could be seen that there existed, in round numbers, a difference of five hours between the meridian of Washington and that of Lincoln Island, that is to say, it was midday in Lincoln Island when it was already five o'clock in the evening in Washington. Now the sun, in its apparent movement round the earth, traverses one degree in four minutes, or fifteen degrees an hour. Fifteen degrees multiplied by five hours give seventy-five degrees.
Then, since Washington is 77deg 3' 11" as much as to say seventy-seven degrees counted from the meridian of Greenwich which the Americans take for their starting-point for longitudes concurrently with the English--it followed that the island must be situated seventy-seven and seventy-five degrees west of the meridian of Greenwich, that is to say, on the hundred and fifty-second degree of west longitude.
Cyrus Harding announced this result to his companions, and taking into consideration errors of observation, as he had done for the latitude, he believed he could positively affirm that the position of Lincoln Island was between the thirty-fifth and the thirty-seventh parallel, and between the hundred and fiftieth and the hundred and fifty-fifth meridian to the west of the meridian of Greenwich.
The possible fault which he attributed to errors in the observation was, it may be seen, of five degrees on both sides, which, at sixty miles to a degree, would give an error of three hundred miles in latitude and longitude for the exact position.
But this error would not influence the determination which it was necessary to take. It was very evident that Lincoln Island was at such a distance from every country or island that it would be too hazardous to attempt to reach one in a frail boat.
In fact, this calculation placed it at least twelve hundred miles from Tahiti and the islands of the archipelago of the Pomoutous, more than eighteen hundred miles from New Zealand, and more than four thousand five hundred miles from the American coast!
And when Cyrus Harding consulted his memory, he could not remember in any way that such an island occupied, in that part of the Pacific, the situation assigned to Lincoln Island.
The next day, the 17th of April, the sailor's first words were addressed to Gideon Spilett.
"Well, sir," he asked, "what shall we do to-day?"
"What the captain pleases," replied the reporter.
Till then the engineer's companions had been brickmakers and potters, now they were to become metallurgists.
The day before, after breakfast, they had explored as far as the point of Mandible Cape, seven miles distant from the Chimneys. There, the long series of downs ended, and the soil had a volcanic appearance. There were no longer high cliffs as at Prospect Heights, but a strange and capricious border which surrounded the narrow gulf between the two capes, formed of mineral matter, thrown up by the volcano. Arrived at this point the settlers retraced their steps, and at nightfall entered the Chimneys; but they did not sleep before the question of knowing whether they could think of leaving Lincoln Island or not was definitely settled.