Rumbling through a gloomy, rock-walled cut traversing the barren range of the Sierra Tortilla, the railroad emerges--after much bumping through scorched foothills and rattling over straddle-legged trestles above dry arroyos--at Mesaville. Mesaville stands on the south bank of the San Pedro, a scanty branch of the Gila River. To the south of this little desert community, across the quivering stretches of glaring sand and mesquite, there hangs always a blue cloud--the Santa Catapina Range. The blazing noonday sun lay smitingly over Mesaville and the inhabitants of that town, when on a September day the dust-powdered train before referred to drew up groaningly at the depot, and from one of its forward cars there emerged three boys of a type strange to the primitive settlement. The eldest of the three, a boy of about seventeen, whom his two friends addressed as Rob, was Rob Blake, whom readers of the Boy Scouts of the Eagle Patrol--the first volume of this series--have met before. His companions were Corporal Merritt Crawford of the same patrol, and the rotund Tubby Hopkins, the son of widow Hopkins of Hampton, Long Island, from which village all three, in fact, came. "Well, here we are at Mesaville." Rob Blake gazed across the hot tracks at the row of raw buildings opposite as he spoke, and the town gazed back in frank curiosity at him. Opposite the depot was a small hotel, on the porch of which several figures had been seated with their chairs tilted back, and their feet on the rail, as the train rolled in. As it pulled out again, leaving the boys and an imposing pile of baggage exposed to the view of the Mesavillians, six pairs of feet were removed from the porch-rails as if by machinery, and their several owners bent forward in a frank stare at the newcomers. "Must think a circus has come to town," commented Tubby. "Well, they know where to look for the elephant," teased Merritt mischievously. "And for the laughing hyena, too, I guess," parried the fat youth, as the corporal went off into a paroxysm of suddenly checked laughter. The boys had bought sombreros at Truxton, and in their baggage was clothing of the kind which Harry Harkness--at whose invitation they had come to this part of the country--had advised them to buy. But as they still wore their light summer suits of Eastern cut and make, their generally "different" look from the members of the Mesaville Hotel Loungers' Association was quite sufficient to excite the attention of the latter. Readers of the Boy Scouts of the Eagle Patrol will recall that in that book was related the formation of the patrol at Hampton Harbor, L. I., and how it had been effected. How the boys of the patrol had many opportunities to show that they were true scouts was also told. Notably was this so in the incident of the stolen uniforms, in which the boys' enemies, Jack Curtiss, Bill Bender and Hank Handcraft, a disreputable old town character, were implicated.