Mrs. Meade and the girls returned by an early morning train, so the two chums did not see the girls again during that visit. On Sunday, Dave went at his books with a dogged air, after morning chapel and dinner. "I suppose this is the last day of study for me here," grimaced Dan, "so I mean to make the most of the pleasure." "Nonsense," retorted Darrin heartily; "you'll finish out this year, and then have two more solid years of study here ahead of you." "Cut it!" begged Dan dolefully. "Don't try to jolly me along like that." "You're down in the dumps, just now, Danny boy," smiled Darrin wistfully. "Just bombard the Board with rapid-fire talk to-morrow, and you'll pull through all right." Dan sighed, then went on with his half-hearted study. Later in the afternoon Dave, feeling the need of fresh air, closed his books. "Come for a walk, Danny boy?" "Don't dare to," replied Dalzell morosely. So, though Darrin went out, he resolved not to remain long away from his moody chum. Outside, on one of the cement walks, Dave turned toward Flirtation Walk. It seemed the best surrounding in which to think of Belle. "Mr. Darrin!" called a voice. Dave turned, to behold Mr. Treadwell coming at a fast stride with a scowl on his face. "That was a dirty trick you played me last night, Mr. Darrin!" cried the first classman angrily. "What?" gasped Dave, astonished, for this was not in line with the usual conversation of midshipmen. "You know well enough what I mean," cried Treadwell angrily. "You spiked my only chance to dance with Miss Meade." "You're wrong there," retorted Dave coldly and truthfully "I didn't." "Then how did it happen?" "I can't discuss that with you," Darrin rejoined. "I didn't make any effort, though, to spoil your chance of a dance with the young lady." "Mr. Darrin, I don't choose to believe you, sir!" Dave's face went crimson, then pale. "Do you realize what you're saying, Mr. Treadwell?" "Of course"--sneeringly. "Are you trying to pick trouble with me?" demanded Dave, his eyes flashing with spirit. "I repeat that I don't choose to believe your explanation, sir." "Then you pass me the lie?" "As you prefer to consider it," jeered the first classman. "Oh, very good, then, Mr. Treadwell," retorted Dave, eyeing the first classman and sizing him up. Treadwell was one of the biggest men, physically, in the brigade. He was also one of the noted fighters of his class. Beside Treadwell, Midshipman Darrin did not size up at all advantageously. "If you do not retract what you just said," pursued Dave Darrin, growing cooler now that he realized the deliberate nature of the affront that had been put upon him, "I shall have no choice but to send my friends to you." "Delighted to see them, at any time," replied the first classman, turning disdainfully upon his heel and strolling away.