The sand was alive with an uncanny, tiny life. Horned toads flopped unexpectedly across the trail. Lizards were everywhere, running over and under the tent floors and along the thatching of the condenser and the engine house. There were many rattlesnakes too, particularly dangerous at this time of year because, Dick said, they were shedding their skins and were blind, striking at any sound. There were Gila monsters now and again. There were many scorpions and centipedes, with once in a while a tarantula. Dick and Charley laid down certain laws of the summer desert. No one was to go to bed without examining the bedding for tarantulas or centipedes. No one was to dress without subjecting every article of apparel to the same scrutiny. No one was to go out at night without a "bug" for fear of the blind striking of a rattler. Every one must learn to kill a snake with a snake stick. And every one, even Felicia, must learn to treat snake bites. Elsa, clear-headed and matter of fact, was very little annoyed by all this gliding venomous summer life. But little Felicia's horror of it was difficult to control. It seemed to Roger that the child's nerves had been uneven ever since the "cologne affair," as Ernest called it. But he could not be sure of this, for Charley insisted that the little girl's fears of all that uncanny fraternity of the sand was exactly what hers had been four years before. August was slipping by, quietly enough when Gustav, returning one day from Archer's Springs, delivered to Roger a letter from Hampton of the Smithsonian saying that on the thirtieth day of August a representative of the Smithsonian would reach Archer's Springs on his way to Los Angeles; that he had but two days to spare but would be glad to give these days to the Moore experiment. Roger was in despair. "Two days!" he groaned. "Why, it takes two days to come up and back. Better stay away." "Don't be an idiot, Rog," exclaimed Ernest. "You get him here, and he'll stay for a day or so. How can he get away? The thing that bothers me is that darned engine of yours." "It doesn't bother me," replied Roger, with a quick gleam in his gray eyes and a sudden smile. "I've got a week before he gets here and by Jove, the old kettle's got to be ready!" He gave a sudden long sigh and looked off toward the distant line of the river range. "I thought it was queer of the Smithsonian to treat me as it did. Ern, this puts new life in me."