"Of all the rotten things to do!" snapped out Nort. "To kill these poor cattle! Why doesn't that gang fight like men if they want to give battle—not spray their dirty poison gas around dumb beasts?"
"It is pretty rotten," agreed Dick.
Bud was carefully scanning the ground in the vicinity of the dead cattle, at the same time cautiously sniffing the air to detect any possible taint. But he seemed to discover nothing. Dick and Nort followed his example, but were unable to come upon any clew.
However, not far from where the half dozen valuable animals had dropped dead there was a little crack or rift in the earth. It was a sort of opening between two long ridges of rocks, there being an outcropping of stone at this point. It was part of the two ridges which, suddenly rising higher, formed the walls of Smugglers' Glen farther to the south. Dick was the first to notice it.
"See anything there?" asked Bud, noting that his cousin was bending over the cleft in the surface.
"No, I can't see anything and I can't smell anything," he added, as he bent closer.
"But I can hear something!" added Nort.
"Hear something?" questioned Bud.
"Yes, the sound of running water down there. Listen!"
He bent with his ear over the crack in the rocks. And in the silence, broken only by the slight movements of their ponies, from which they had dismounted, the boys heard the murmur as of water flowing along far under ground.