“This reserve supply, in a powerfully concentrated form, I now have with me.”
“Oh! Isn’t it dangerous, old man?” I asked, glancing around uneasily.
“Properly applied it might blow all Panama to atoms,” he returned vaguely. “But it cannot be accidently exploded while it remains in the place I have provided for it.”
“Where is that?”
He reached down and removed a square trap in the floor of the car. Leaning over, I discovered a small cylindrical jar, having the capacity of about a quart, which was suspended at one side of the driving shaft. The straps that held it in place allowed it to swing in any direction with the movement of the machine, but any sudden jar was impossible.
“Is it like nitro-glycerine?” I asked, eyeing the cylinder with an involuntary shudder.
“Not at all,” replied the inventor, calmly closing the trap again. “It is a much more powerful explosive, in its concentrated form, but may be diluted to any strength desired. The mechanism I have invented for its application renders it perfectly harmless when exploded in atomic quantities in the engines, although ordinary concussion would, as in the case of nitro-glycerine, explode the condensed contents of the extra cylinder.”
“I think I now comprehend your idea,” said I.
“Yes, it is very simple. Under cover of darkness I propose to bore a hole in that barrier and fill it with my explosive. In the morning I will blow up the wall and in the excitement that follows run the machine through the gap and escape.”
“Very good!” I exclaimed, joyfully. “Then all we need do is to keep these Indians at bay until we have an opportunity to do the job.”