CHAPTER IX
THE ERUPTION
AY and night the stream of noxious vapors and molten matter poured forth from the newly created volcano; and a most magnificent spectacle it formed. But, interesting as it was to watch these brilliant fireworks, there was not one of our friends who did not ardently desire the display to stop, that the work of digging the tunnel might be resumed.
Even Flora Curtis was as impatient as the rest, though she took great delight in climbing up into the doctor's observatory to watch the immense sheaf of flame rise into the sky, and then drop down, a great distance away, in graceful curves of fire. Fortunately, the observatory itself was protected from the heat by means analogous to those used to keep the tube from melting.
The submarine boats were in continual demand, not only for the use of the workmen, but also for the transportation of visitors, thousands of whom flocked to see the new volcano.
As for Dr. Giles himself, he seldom left his office, except for the purpose of ascending into the observatory to watch the eruption, endeavoring to discern whether or not there were any indications of a diminution in the volcanic flow.
His constant supervision was necessary for the important task of securing a free outlet for the electricity produced in the tube; for if, through any inadvertence, this electrical energy was not disposed of as fast as it was created, it would do one of two things: it would either find a vent for itself, at the risk of causing considerable damage, or, if pent up, it would check the further conversion of heat into electricity, and the carbonite tube would then melt at once under the influence of the excessive heat.
Fortunately, as we have said, there was a ready market in Australia for more electricity than the doctor could produce; so that, although his supply was now many times greater than it had been before the eruption,—the whole interior surface of the tube being at present engaged in the work of transforming heat into electrical energy,—the doctor was unable to fill all the orders he received. Nevertheless, the coffers of the company were filled to overflowing with the receipts from the sale of this electrical power. In fact, the vexations delay caused by the eruption was destined to prove of the greatest financial benefit to the stock-holders.
The important task of keeping the apparatus in perfect running order the doctor would confide to no one except to his chief engineer during the intervals of time when he himself was obliged to sleep; and even then it was only with strict orders that he should be awakened at the least sign of irregularity in the working of the current on either side—for special wires kept him in constant communication with the New York end of the tube.
To be obliged to wait thus with folded arms until the volcanic activities had quieted down was exceedingly discouraging, and the only hopeful sign the doctor saw was that there was a large proportion of vapor mingled with the molten matter hurled forth by the volcano. This led him to believe that only a pocket had been struck. Such, indeed, seemed to be the case; for after four months of weary waiting the eruption gradually subsided. 
"DAY AND NIGHT THE STREAM OF NOXIOUS VAPORS POURED FORTH."
Fortunately, the amount of matter ejected was relatively small, and nothing of the kind occurred. Work was therefore resumed, and pushed to completion with the utmost rapidity.
It was somewhat discouraging to be obliged to begin over again what had already been done, but there was no help for it; so the tube was cleared of the molten matter that had gathered there, and the work of digging was then continued, with instruments of still greater complexity than before, to meet the new conditions in the tube.
Day and night did the work continue, there being six relays of workmen, each serving for four hours at a time, assisted by dynamos of undreamed-of power; and as fast as the hole was deepened the tube was lengthened and lowered. Every possible precaution was taken, and less than five years after the first eruption the two tubes were within a single mile of each other.
During the entire previous portion of the work Dr. Giles had managed to maintain his calm outward appearance; but now, as the tunnel approached completion, he could no longer conceal his agitation, but paced to and fro like a caged animal.
"Why, whatever is the matter with you, doctor?" asked James Curtis, who had dropped in, as usual, with his daughter Flora, who was now a charming girl of fifteen, and as brimful of sympathy as ever.
"The matter is, James, that to-day I am to learn whether or not the tube is finished, or whether it will require five more years of hard work to complete it."
"Why, what in the world do you mean? Are n't your two tubes now within a mile of each other, and won't they touch to-night?"
"I sincerely hope so," said the doctor; "but it is quite possible that they will never meet."
"How so?" inquired Mr. Curtis, quickly.
"Well, the thing is this. Even in constructing a tunnel a few miles long, our engineers, if they begin work at both ends at once, find the greatest difficulty in making the two holes meet. Moreover, in their tunnels a small error is of no material consequence. Now in my case I am digging a tunnel eight thousand miles long, and have begun work at both ends. Besides, I have only been able to allow a margin for error of three feet at the point of meeting. A margin of three feet on eight thousand miles is, as you can readily calculate for yourself, only a margin of one two hundredth of an inch on each mile! In other words, if, in digging my tunnel, I have made an error of one two hundredth part of an inch on each mile, or, at least, if these errors do not compensate, my tubes will not meet, and half the work will have to be done over again!"
"Whew!" whistled Mr. Curtis. "And you knew this when you started to build the tube?"
"Perfectly," said Dr. Giles; "and I was accordingly obliged to devise instruments of almost impossible delicacy of operation to use in aiming my tubes. The next twenty-four hours will show me whether or not my aim has been true, or whether we shall have five years more of weary working and waiting. Do you wonder now that I seem agitated, and that I cannot stay quietly in place, but pace up and down like a caged animal?"