As the others attempted to speak, he bade them be silent until he could solve this problem.
Looking down, his eye fell upon the iron bar which the workman had let slip through his hand in opening the breach. It rested just under the aluminum rod attached to the wheel-work. From the bar his eyes wandered inquiringly from one to the other.
“It shlipped out of me hond in making ther hule,” said the man who had dropped it into the chamber.
The mystery was solved. The iron bar, in slipping through the workman’s hands into the chamber, had struck the aluminum rod and set the wheel-work in motion; everything else had worked perfectly, and as Cobb had designed that it should work. But one other thing troubled him very much, and that was why did the compass-needle mark 899 instead of 260, as it ought to do?
“Give me a pencil and paper,” he said to Rawolle, “and be still but a moment, and I will answer your questions.”
The materials were given to him, and he busied himself a moment in putting down some figures.
“Yes, as I thought,” he soon exclaimed, throwing down the pencil. “It was I who made the mistake. Gentlemen, you see that needle marking 899,” and he pointed it to them. “Well, a hundred and thirteen years ago, or, more accurately, in December, 1887, it marked 1,007.8. I computed that it would move to where that catch now is, at 260, in one hundred years; but, like many another man, I made a most simple error. In my work, I read 14.355, instead of 1.4355—the mere misplacing of the decimal point. It came near costing me my life. Instead of the needle moving 732.7 points, as I thought it would, it moved but 73.27 points in the hundred years that I anticipated remaining here. It has moved only 108.7 points in one hundred and thirteen years.”
It was well that Cobb had made this great mistake, for the movement of the magnetic meridian was, in reality, so slow on the meridian of San Francisco, that he could not have used it with any degree of safety. One hundred and eight points, or an arc of 1 degree 48 minutes, was too small to work upon, as any great magnetic storm, earthquake, or other disturbance might have caused it to oscillate over such a small arc and spring the wheel-work. In fact, the needle, as Cobb had set it, would not have arrived at the little catch before the middle of June, A. D. 2198.
Without losing another moment, Cobb wrapped himself in a heavy overcoat taken from the iron box, and requested Rawolle to take the other box with him, and to take him to a hotel at once, as he needed rest and refreshment.