“You remember that rumor we heard before we left Brewster,” he said; “about the Overland Central planning to get a railroad into Little Ophir ahead of us?”

Dick nodded, and Larry went on.

“I was just thinking. The only way to reach Little Ophir with a railroad track is up this canyon; and from what we’ve seen of the canyon this far, you’d say that there isn’t room for more than one railroad in it, wouldn’t you?”

“Wow!” said Dick, springing to his feet; “you sure said a whole mouthful that time, Larry! But see here—we located this canyon line first, years ago. If this is an O. C. survey that we’ve found, they’re cutting in on us! Let’s hike back and tell Mr. Ackerman, right away. We oughtn’t to lose a minute!”

Now haste was all right, and, in the circumstances, was doubtless a prime factor in whatever problem was going to arise out of the clash between the two railroad companies. But along with his Irish blood—which wasn’t Irish until after you’d gone back three or four generations—Larry Donovan had inherited a few drops of thoughtful Scotch.

“Hold on, Richard, you old quick-trigger; let’s make sure, first,” he amended. “Maybe we can trace these markers and find out where they lead to. When we make our report we want something more than a wild guess to put in it—not?”

The tracing, which took them back down-canyon, proved to be a regular detective’s job. Great pains had evidently been taken to hide all the markings of the strange survey. At each fifty measured feet they stopped and searched; hunted until they found what they were looking for. Sometimes it was a stake driven down level with the surface of the ground and covered with a flat stone. In another place the marks would be on a boulder, with another stone stood up in front of them to hide them.

Roughly speaking, the newer survey paralleled the older, fairly duplicating it in the narrower parts of the gorge, where there was room for only a single line of track; which meant, as Larry pointed out, that the first builders to get on the ground would have a monopoly of all the room there was. As they went on, the chase grew more and more exciting, and they began to speculate a bit on the probabilities.

“If this is an Overland Central line it must come in from the north, somewhere,” Dick argued. “To do that, it will have to cross the Tourmaline to get over to our side of things. We must watch out sharp for that crossing place.”

So they watched out, making careful book notes of each freshly discovered set of marks as they went along. Luckily, their chief had early made them study the abbreviations used by the engineers in stake marking; “P.I.,” point of intersection of a curve, “C—4.6,” a cutting of four and six-tenths feet, “F—2,” a fill of two feet, and so on. These figures Larry was copying into his note-book as they occurred on the various stakes; and finally, squarely opposite the mouth of what appeared to be a blind branch gulch coming into the main canyon from the north side, they found one of the carefully hidden stakes with this on it: “Tang. W.3-S.,P.I.,N.12-W.”