Hour after hour they went from one pond to another. The ponds were larger and wilder at each crossing, and already they were in a wilderness of woods and lakes, and heard the whistle of the hawk, the scream of the lonely eagle, and the crazy cries of the loon. Every once in a while a big heron mounted lazily upward and flew off solemnly to a place where his peace need not be disturbed. [Illustration: _A._ Moth. _B._ Caterpillar. _C._ Side view of head of moth. _D._ and _E._ Scales from the wing of a butterfly.] Although Hope and Peter and Jack lived all the year around in Rangeley Village, yet they had never been so far away from home before, and to them it seemed very wonderful. Even in the midst of it all, however, Jack did not forget the prize Ben Gile had offered. He hurried over carry after carry, and at the end of each one might be found flat on his face studying some little hill of ants. At last, after travelling five hours, they came to a halt, ravenously hungry. Dinner was cooked and eaten, and then, after dinner, they began their long ascent of Saddleback, for they were going to a lonely little pond on the second highest mountain in the State of Maine. There, at Camp-in-the-Clouds, was a cabin in which Mrs. Reece could sleep, and the girls, too, if they wished, although they declared that they would not. Up, up the hill they trudged, stepping over blow-downs, following their footing carefully, and watching with interest the little animals that scampered out of their way. But never did packs grow so heavy, and at last Mrs. Reece, who was carrying nothing but Jack's camera, sat down panting and laughing. "I can't go a step farther," she declared, "until I catch my breath." "This is a good place to rest," assented the guide. "Some deer found it so this morning, I think. Here, catch that butterfly, Jack!" In a flash Jack had caught the butterfly, and brought it, gently, to Ben Gile. "You don't see this fellow up here often. Who knows the difference between a butterfly and a moth? No one? Well, that is because most children are going to bed about the time the moth begins to fly. Doesn't any one know? You have all seen moths and butterflies? Well, well, well! "The first thing you see is that when the moth lights on the edge of a flower-cup, instead of holding the wings up above the body, as the butterfly does, it spreads its wings flat over the body. Then a butterfly has little knobs at the tips of its slender antennae, while the moth has slender ones without knobs, or pretty, feathery ones that look like plumes." "I supposed," said Peter, "that moths and butterflies were just the same, except that moths will fly into the house and burn their wings on the lamps." Peter didn't in the least care about moths and butterflies. He was longing to get to the top of the mountain, but he was too polite to seem impatient.