"If it was done at all—which I'm not saying for a fact—it probably was done by the same man, or men, who have been doing the other killings in Death Valley."
"But what in the world for?" exclaimed Dick.
"Search me!" answered Bud.
"The other cows weren't shot!" asserted Nort. "Sam's horse that died wasn't shot, and no bullet nipped him or even creased him."
"No," agreed Bud. "I guess I'm out when it comes to guessing those cows were shot. But let's wait a bit before we go any closer. We can't do those dead cows any good and it may save our lives."
Though their curiosity made them eager and anxious, the boy ranchers held themselves in check and while riding slowly around on their ponies kept a keen watch of the territory surrounding the grazing herd and the motionless forms of the dead cows.
But when nearly half an hour had passed, and there was no sign of any human enemy, and when nothing suspicious had been observed, Bud gave the signal to ride on to come closer to the scene of the mystery. During the wait the living members of the herd had exhibited no signs of uneasiness. They wandered around, grazed, ambled here and there, some coming close to look at the boy riders. They behaved like any normal herd of cows. Some of the calves showed their playfulness in kicking up their heels and darting hither and yon, while some of the young bulls engaged in head-butting contests.
"Whatever happened," said Bud as he and his cousins rode nearer, "didn't scare the whole herd. Death must have come silently, and in the night."
"Silently, I grant you, but not necessarily in the night," spoke Dick.
"It could happen any time, as it did to Sam. That was in the daytime."
"You're right," Bud admitted. "It sure is mighty queer. But maybe we can find out, now that it has happened almost under our noses as you might say."