"You'll soon see," was the answer. Only skillful cowpunchers could have made their way through that maddened, seething, wild herd of cattle. But Dave, Mr. Carson and Skinny were more at home in the saddle than afoot. Their intelligent ponies pushed their way through the heaving mass of steers until the three of them stood on the brink of what had been a fair-sized branch of the Rolling River but a few hours before. Now all that showed was a small, narrow ribbon of muddy water, in the clay-like expanse of what had been the bed of the original stream. "Whew!" whistled Mr. Carson. "This sure is bad!" "I should say so!" exclaimed Dave. A sharp bend in the course of the stream above them cut off all but a very limited view. But, as far as they could see, the same conditions prevailed. There was only a small trickle of water. It was in the very middle, the lowest point of the stream, and up to the very edge of this the thirst-tortured cattle pressed, sinking down deep in the soft mud. "We've got to get 'em out of that," declared the ranchman. "A lot of 'em will be mired if we don't." "There are some mired now," said Skinny, pointing. "Ed and Foster are trying to yank 'em out." He indicated two cowboys who, with ropes around the mired steers, were trying to drag them to solid ground. Other animals, though, were pressing in to make their way to the water. It was a hot day, and bore a promise of being hotter. It needed but a glance to show that the water would soon fail entirely. And it was evident what had caused it. At some point, higher up, the supply had been cut off or diverted. "Well," said Mr. Carson quickly, like a general on the field meeting a reverse, and deciding on the best way to save the day, "well, the only thing we can do is to get the cattle off this range. Take 'em over to the spring, Skinny-you and the rest of the boys. Fight 'em hard-it's the only way. I'll ride on up and see what's happened to our water supply. Dave, you ride back and get Mr. Bellmore. Maybe he can tell us a way out of this trouble. He's a water engineer." Thus were the orders issued, and the cowboys and Dave prepared to carry them out. Hardly had Mr. Carson ceased speaking than Skinny rode off with a whoop to aid his fellows. Dave watched for a moment as the cowboys prepared to move the herd of valuable cattle. It would be hard work to get them away from the water while a drop yet remained in the muddy pools. But it must be done, for if the steers were allowed to remain there many of them would be mired, and in the fight for water others would be trampled on and killed. As Dave galloped back to the ranch to summon the irrigation engineer he saw Mr. Carson head his pony for the bend, above which was the beginning of the Centre O ranch. Then the young cowpuncher gave a look at the strenuous efforts of the cowboys to move the maddened cattle. "They'll have their own troubles," Dave reasoned. "I'll help them as soon as I get back."