CHAPTER XXXI
IN WHICH DR. GILES RECEIVES A SHOCK
T the very moment when the warning of danger appeared to William in his car, a similar sign appeared in Dr. Giles's office, where that gentleman was closeted with Mr. Curtis and Flora. For some little time past the doctor had noticed with growing anxiety an abnormal fluctuation in the electrical current from the tube. Evidently something was the matter, but what could it be? In vain the doctor tried every conceivable remedy; the trouble increased, and finally the danger-signal itself appeared, warning him that matters had reached a crisis, since this signal was only set for a high amount of disturbance in the current.
The effect of this signal on the three spectators may be readily imagined; but on Flora Curtis it was especially potent. The poor girl buried her face in her hands, and burst out sobbing.
"FOR SOME LITTLE TIME FAST, THE DOCTOR HAD NOTICED WITH GROWING ANXIETY AN ABNORMAL FLUCTUATION."
"Nonsense," said the doctor, kindly. "You had nothing whatever to do with the matter, Flora. I had fully made up my mind to let William go before you spoke a word. Besides, matters are not so bad as they seem. If the danger can only be warded off for half an hour more, William will be in safety on the other side. Every instant we gain now is so much toward his salvation. Come, dry your eyes; for I shall need you to help me watch the instruments, and on the promptness of our actions everything may now depend.
Thus admonished, Flora quickly brushed away her tears, for in the hope of being of use to our hero she would have risked anything and dared anything. But as she turned to the instruments, a cry of alarm from the doctor caused her to look up.
At the same moment an ominous rumbling was borne to her ears, and closely following it came a more pronounced irregularity in the working of the electric conductors which served to keep the tube from melting.
Dr. Giles heard this rumbling too, and the whole truth flashed upon him in an instant. Something must have happened to the tube! The devices for converting the heat into electricity must in some way have become injured, and now refused to work properly.
The doctor's face blanched as he realized the full meaning of these signs.
Evidently, if the apparatus was out of order, the internal heat of the earth, having no longer a free outlet, would rapidly accumulate, producing such a temperature that the tube would melt; and what would then become of the brave boy who had dared this unknown danger for the sake of his mother?
With set faces, our three friends watched the instruments, when suddenly they were startled by a loud report like distant thunder, accompanied by a shock that set the whole office vibrating. Dr. Giles cast one agonized look at the instruments, and then fell back in his chair.
"William is lost!" he cried in anguish. "The carbonite tube has given way. The poor boy's death is certain; for I am absolutely powerless here, and can only stand idly by and let matters take their course!"