He leaned back and pointed with the pencil.
“Consider that you are above the hill in an aeroplane, looking down,” he began, “and that you have the gift of seeing through earth and stone. ‘EE’ represents the hill. ‘A’ is the tunnel. ‘B’ is the point to where the tunnel had progressed when the slide occurred, and also the gap through which the muck is sliding. ‘D’ represents the slide. ‘C’ is the other end of the tunnel. You could abandon the ‘A’ end and complete the tunnel by working the ‘C’ end only, of course, but you are not able to work enough men on one end to complete the job on time and as per contract. You must have two gangs working toward each other. But a slide occurs at ‘B’ which you cannot stop. It strikes me that the rock roof is thinner at ‘B’ than you found it while working toward ‘B,’ or else the slide would have occurred before it did. This being the case, I assume that the rock stratum is heavier on both sides of ‘B,’ all around it, in fact, than it is at ‘B.’ So all that we have to do is to work our way around ‘B’ and approach it from the other end.
“And to do this in the least possible time I suggest a coyote hole—‘F,’ ‘G,’ ‘H’ and ‘I’—a very small tunnel through what in all probability is solid stone, the workmen timbering up ahead of them and shooting very light. Especial care must be taken when they make the turn from ‘H’ to ‘I,’ and all along ‘I’ until the slide is reached. Then when they reach the slide let them timber soundly, and continue timbering through the slide until they reach the other end of it. And when all is timbered, you can go right ahead with your big tunnel with no fear of another slide. Is that all clear?”
For fully a quarter of a minute nobody spoke. All stood studying the diagram. Then came the heavy voice of the first expert engineer who had come from the East.
“Utter rot!” he opined. “Tell me, will you, why we will be able to work through the slide and timber up ahead of us any easier from your small tunnel, ‘I,’ than from where we are now? Your idea is a howling farce.”
“I’m sorry you think so,” said Joshua, very red in the face. “But my plan hinges on the feature that the slide is traveling in a slanting direction toward ‘B.’ And the coyote hole, ‘I,’ runs into the slide from the other direction. You have no roof above you now to hold back the slide. But ‘I’ has been run through solid stone, and has a solid roof above it. And when you timber from ‘I’ into the slide, you haven’t the pressure against you that you have at the other end of the main tunnel. You’ve worked behind the pressure, can’t you see?”
Another moment or two of silence, then from Philip Demarest: “Heavens to Betsy, boys! He’s right! It’s simple as the nose on your face, and a ten-year-old kid oughta figgered it out. Do you see it, boys? Do you see it? This bird gets behind the pressure of the slide instead of buckin’ it. God, but we’ve been a pack of fools!”
“Oh, Mr. Demarest!” cried Madge. “Do you mean it? Do you actually mean it?”
“I mean we’re gonta try it as quick as we can get to work!” he yelled excitedly. “It may not work at all, but it’s the only sensible thing that’s been advanced since the timbers and baled hay failed to hold her. And if she does work—this bird’s not only made his five thousand bucks, but he’s got a job that he won’t be ashamed to tell his folks about.”