The old man looked at the young inspector pityingly. "Owen--er--I beg your pardon, I mean Mr. Sheridan--I’m mighty sorry that they sent you up to handle this case, because I’ve decided, after thinking it over, that I’d better tell the whole truth, and I’m afraid it’s going to hit you pretty hard." "Hit _me_ hard!" exclaimed Owen, in astonishment. "Yes, sir. I’ve kept quiet until now--first, because in order to tell the truth I’ll have to confess to having violated the rules, which I hate to do, having been so long in the service; secondly, because I don’t like the idea of causing trouble to the young lady." "The young lady!" Owen couldn’t help breaking in. "Yes. As I say, I’ve decided that I’d better tell the truth," said Pop Andrews. "I do know something about that letter. There was a pink envelope in the box when I went to collect the mail. I gave it to the young lady who was standing at the box waiting for me. At first I didn’t want to give it to her, knowing it was against the rules, but she begged so hard, and finally, when she began to cry, telling me that it meant all the world to her to get that letter back, I decided that I’d take a chance, and I handed her the pink envelope." "She told you that it was hers, of course, Pop?" said Owen. "Yes; she said that she’d dropped it in the box only five minutes before, and that it was a letter that would cause a lot of trouble if it was sent, so she wanted it back. I believed her, and I let her have it, not dreaming that it wasn’t hers--that she was working a game on me." "And I suppose you have no idea who this young woman was, have you, Pop?" Once more the gray-haired carrier looked pityingly at the young inspector. "Yes, Mr. Sheridan, I have. I hate to tell you, knowing what she is to you, but it was the young lady who works in Mr. Sammis’ office, Miss Dallas Worthington." Walking so quickly that his pace was almost a run, Owen Sheridan hurried around to Walter K. Sammis’ real-estate office. It was past ten o’clock, and Dallas was usually at her typewriter by nine; but there was no sign of her now. Her employer stood in the outer office, and looked at Owen questioningly. "Hasn’t Miss Worthington got down yet, Mr. Sammis?" the young man asked. "No, she hasn’t, and I can’t understand what’s keeping her." Without stopping to say another word, Owen hurried around to Dallas’ boarding house. It was ridiculous, of course, to suspect that she could have stolen that letter; but the mystery must be cleared up immediately. "Where’s Miss Worthington?" he inquired of the landlady, who came to the door in response to his ring. "I couldn’t tell you, Mr. Sheridan," the woman answered; "she left here last night." "Left last night!" repeated Owen blankly. "Yes; she came in here just before supper time, rushed up to her room, packed her suit case, and hurried out of the house as if a thousand demons were after her." CHAPTER XVI. THE PINK ENVELOPE.