“The same stuff that blew Mrs. Bijur’s roof up?” gasped Tom, but without a hint of laughter in his voice or on his face. He began to see what was in the wind now.
“Yes,” was the rejoinder; “at least what exploded there was not more than a hundredth part of this tube, and it was not of anything like similar strength, being diluted. I had this explosive with me on the yawl, thinking that I might use it in geological work—diluted, of course. When the collision came I recollect seizing up this tube of my invention and thrusting it into my coat. In this rush of recent events I had forgotten it till this moment, when, in my search for a pencil, I encountered it.”
“What do you mean to do with it?” asked Tom, in the same breathless tones. Without knowing it, he was clutching the professor in the intensity of his excitement and eager hope.
“I mean to attempt to blow up the rock that blocks the entrance of this cave,” was the calm reply. “We have tools—a drill, and we can use that long stick I cut as a walking staff, for a tampon to drive the charge home.”
“But how are we to fire it?” asked Tom. “We have no fuse and no means of getting one.”
“Confound it!” exclaimed the professor, his hopes dashed to the lowest ebb once more. “What a fellow I am to forget details. What are we to do? Here we have the means of escape within our grasp almost, only to see them snatched away by such an unlucky chance as this. In any event, an ordinary fuse would do us no good. My explosive only ignites by detonation—in other words, by being dealt a hard blow. If only we had a fulminate of mercury cap——”
“Might as well wish that the stone hadn’t fallen,” said Tom briskly. “I tell you what, Professor, let us start those Kanakas drilling a hole in the rock where it seems thinnest. While they are doing it we, perhaps, can think of some plan to explode the charge.”
It is a striking example of the effect of action on men that the Kanakas, once they were set to work, became far less gloomy. They tapped the rock eagerly to ascertain, while the professor listened to see, where it sounded the least solid. He finally selected a place and ordered the two South Sea natives to commence their bore there. They at once set to work at the task, while Mr. Chillingworth, who had been roused from his lethargy by even this remote chance of gaining freedom, talked over eagerly with the others the possibility of hitting upon a way to explode the charge and shatter the stone without using a detonator. The rancher had had considerable experience with dynamite and giant powder on his ranch, where he had blown up scores of big tree roots, so that his contributions to the discussion were intelligent ones.
At last he sprang to his feet with a sharp cry: “I’ve got it. I know how we can explode that stuff.”
The others looked eagerly.