They were both rather silent, Miriam, her momentary lapse into her old, gay self, having dropped back into a depression deeper than before, while Trenholm watched her with an absorption of which he was totally unaware. "I'm afraid you will be late for luncheon," he remarked, happening to glance at his wrist watch as he put his hand on the bridle rein of the mare. "It doesn't matter," she replied absently. "It won't inconvenience them, for Martha doesn't expect me. I should be asleep, you know." "You should indeed," he said, and she wondered at his emphatic tone. "This is no preparation for night duty." "But I am not going on duty to-night," she broke in. "I'm leaving the case." "What?" Trenholm stopped abruptly and eyed her in concern. "Fired?" "No, indeed!" She flushed hotly. "Do you suppose I can take care of Mrs. Nash after her husband's treatment of me?" He did not answer at once. "So you are running away," he commented softly. "Frankly, I did not expect it of you." "Mr. Trenholm!" "Running away," he reiterated, paying not the slightest attention to her indignant ejaculation. "Running away under fire." "Nothing of the sort!" she flared back. "Do you suppose I'll stay in any house where I've twice been called a liar?" "I'm afraid you'll have to," he retorted, with equal heat. "You cannot leave Abbott's Lodge, Miss Ward." "What?" She gazed at him astounded. "Why not?" "Because you are the last person known to have seen Paul Abbott alive," he pointed out slowly. "And your statements regarding the events of Monday night are unsubstantiated." Miriam stared at him as if unable to believe her ears. "Do you insinuate I lied?" she demanded. Trenholm's hand on his horse's rein tightened until the knuckles shone white, but his glance did not waver. "It is not a question of my opinion one way or the other," he said sternly. "You are our chief witness, and as sheriff of Prince Georges County, I cannot permit you to leave Abbott's Lodge." Miriam regarded him intently. "So that is your attitude," she said, finally. "I am glad to have it defined. You have, at least," with a ghost of a smile, "been honest with me." "Thank you!" Trenholm drew a step nearer. "Your reasonable acceptance of the situation encourages me to ask a personal question." "Yes?" she prompted, as he paused. "Well?" "What is your interest in the black seal?" Miriam stared at him, thunderstruck. "The black seal?" she repeated. "Yes--the seal which you have traced many times on paper," and from his coat pocket he drew a number of papers, and held them so that Miriam could see the drawings she had made at odd moments while in the sick room. They were cleverly done--distinct and clear in every detail. Miriam looked first at them and then up at Trenholm, standing silent and stern by her side. "Those drawings were in my bag last night," she stammered. "How did you get them?" "I examined your bag," calmly.