On a sunny September afternoon two shelter tents stood in a mountain valley, on the south bank of a creek which, miles and miles below, becomes the Sweetwater river. Above the flap of each tent lifted a yellow pennant, in the center of which a blue beaver stood in an alert and listening attitude, his flat tail outstretched. A campfire blazed in front of the two tents, and some distance away four bronchos fed noisily on the sweet grass of the valley. Tinned provisions and cooking utensils were scattered here and there in front of the blaze, and four boys wearing the khaki uniform of the Boy Scouts of America were busily engaged in preparing supper. Those who have read the previous