"A soldier's daughter must be--it's part of her life." He tied their horses to the low hanging limbs of a cluster of scrub trees, and found a seat on the bowlders which the Indians had set for a landmark on the lonely hilltop. Westward the plains stretched, a silent ocean of green, luscious grass. "What's that dark spot in the valley?" the girl eagerly asked. "Watch it a moment--" They sat in silence for five minutes. "Why, it's moving!" she cried. "Yes." "How curious--" "An illusion?" he suggested. "Nonsense, I'm not dreaming." "I've been dreaming a lot lately--" A smile played about the corners of her fine mouth. But she ignored the hint. "Tell me," she cried; "you studied the sciences at West Point, what does it mean?" "Look closely. Any fifteen-year-old boy of the plains could explain it." "Am I so ignorant?" she laughed. "No," he answered soberly, "our eyes just refuse to see things at which we are looking until the voice within reveals. The eyes of a hunter could make no mistake about such a spot--particularly if it moved." "It might be a passing cloud--" "There's none in the sky." "Tell me!" she pleaded. "A herd of buffalo." "That big black field! It must be ten acres--" The man laughed at her ignorance with a sudden longing in his heart to help and protect her. "Ten acres! Look again. They are twenty miles away. The herd is packed so densely, the ground is invisible. They cover a thousand acres." "Impossible--" "I assure you, it's true. They were once even more plentiful. But we're pushing them back with the Indians into the sunset. And they, too, will fade away into the twilight at last--" He stopped suddenly. He had almost spoken a sentence that would have committed him beyond retreat. It was just on his lips to say: "I didn't take such tender views of Indians and buffaloes until I met you!" For the life of him he couldn't make the girl out. Her voice was music. Her laughter contagious. And yet she was reserved. About her personality hung a spell which forbade familiarity. Flirting was a pastime in the army. But it had never appealed to him. He was not so sure about her when she laughed. And then her father worried him. The fiery old Southerner had the temper of the devil when roused. He could see that this second daughter was his favorite. He had caught a look of unreasonable anger and jealousy in his eye only that afternoon when they rode away together. Still he must risk it. He had really suggested this sunset scene for that purpose. The field was his own choosing. Only a coward could run now. He managed at last to get his lips to work. "Since you came, Miss Sarah--I've been seeing life at a new angle--" he paused awkwardly. The red blood mounted to her cheeks. "You have given me new eyes--" [Illustration: "'You have given me new eyes'"]