It was a delicious morning in early May, and the sun was at his back, its warm rays falling upon him with affectionate caress. But the lad was plainly oblivious of his immediate surroundings; in spirit he had followed the leading of his eyes a league or more to the westward, where a mass of indefinable shadow bulked hugely upon the horizon line. Indefinable, in that it was neither forest nor mountain nor yet an atmospheric illusion produced by the presence of watery vapor. It did not change in density as does the true cloud; for all of its mistiness of outline there was an impression of solidity about its deeper shadows, something that the wind could not lift nor the light pierce. A mystery, and the boy devoured it with his eyes, his head bent forward and his shoulders held tensely.