"It was wonderful of them, wasn't it!" exclaimed Charley. "I had no idea they felt under obligations, to me. I certainly didn't want them to." Roger nodded and looked at his watch. "It's only nine o'clock now. If it wasn't so frightfully hot and there were any place to go, I'd say let's continue our spree." "Just beyond that strip of desert there," Charley pointed into the valley to the east, "there are some wonderful Indian inscriptions on some rocks around a spring. I've never seen them, but I've always wanted to and I know the trail. Dick has shown it to me." "Let's try it," said Roger. "Peter, come on, you're getting fat and lazy. I believe it's about ten degrees hotter than usual." It was an hour's climb down into the valley. It lost its level look on near inspection. In every direction a fine, powderlike sand lay in long undulating ridges. Neither rock nor cactus was to be seen. A faint wind was stirring and tiny eddies of sand rose against the sky. "You see that peak, due east?" asked Charley. "Well, the spring is just at the foot of that in a little canyon. There's never any trail here at all, the sand drifts so." "I'm glad we're heading for a spring," exclaimed Roger. "I know I can empty the gallon canteen by myself." They started ahead, Roger leading, Peter following behind Charley. It was heavy slow walking. After perhaps an hour of it, during which conversation languished more and more, Charley said, "I don't feel as eager minded as I did about Indian writings, do you?" "Well," replied Roger, stopping to wipe the sand from his face and to grin at Charley. "I wasn't eager about the hieroglyphics to begin with. I haven't taken a girl for a walk for years and I thought this was my chance!" "How is your enthusiasm for that standing up?" chuckled Charley. Roger cleared his throat. "You see, it's like this--" he began, his eyes twinkling. Charley interrupted by catching his arm. "Look, Roger! There's a sand storm coming!" Roger looked up the desert to the north. The familiar gray veil of sand was plainly visible. "Lord!" he exclaimed. "We'd better start back at once." "No, we're within a mile of the spring, now," said Charley. "We'd better get there as fast as we can. I do hope Gustav and Elsa will be all right. That poor new field of alfalfa!" "Perhaps it won't be so bad in the other valley. Certainly this sand is going to try its best to suffocate us. Whew, there she comes!" as a cloud of sand enveloped them. They paused long enough to adjust their bandannas across their faces, then started hurriedly on, Roger holding Charley by the hand and catching Peter's lead rope firmly. In ten minutes the peak toward which they were heading was obscured. "Shall we stop or press on?" shouted Roger. "Let Peter lead!" cried Charley. "If he stops, we'll stop."