Two boys spend their school vacation cutting hay on an older brother's Nevada ranch and later -- joined by younger brother Jason -- they go camping ""prospector style"" in the nearby hills. Their summer is as episodic as the title would lead you to expect, and so much fun it has to come straight from the memories of some real pint-sized buckaroo. While Si and Bren get used to the routine of operating the horse-drawn hayracks (this is the 1920's) they soak up stories about their fellow workers -- particularly the 300 pound Patrick Henry who tames a wicked work horse named Dirty Jasper, the blacksmith Ben whose speech is pocked with deleted ""(dirty words)"" and the Chinese cook who conquers the balky, mysterious new telephone. Then Si rescues a down and out mare which he hopes to model after his brother's racing Dolly. . .and the boys' camping trip (at first, more of a traveling feast than anything else) turns to terror when they shoot two rattlesnakes and hear dozens, maybe hundreds, more buzzing in the sagebrush. Kent doesn't bother to tell what, if anything, the boys learn from their big scare; in fact, we get to know the ranchhands and their mounts better than the boys themselves. But with all the limitations of a campfire tall tale, this is a winner.