Hilary remembered that Miss Carson invariably wore the watch and chain, so that this small key evidently fitted something that she was careful always to keep locked up. As Hilary picked up this key the chain slid away from it, and she saw that the spring of the swivel was broken. That accounted, then, for the fact that Miss Carson was not wearing her watch, as she usually did. And when she left it on the dressing-table she had evidently forgotten that she was leaving the little key, which as a rule she was so careful to wear, lying about too.
Criminals, Hilary reflected with immense satisfaction as she picked up the key, always did forget important things of that sort. Now what did that little key fit? Evidently some bag or some small box which contained something that it behoved her to keep carefully concealed from every eye but her own. Now, where could that bag or box be, Hilary wondered, as she glanced round the room. Were there any drawers or cupboards that she had not yet thoroughly searched? Yes, there was the big bottom drawer in the wardrobe, in which Miss Carson kept her hats. She had looked into it once, but seeing that it apparently contained nothing but the few simple hats that the holiday governess owned, had pushed it to again. But now, feeling that that cursory glance had not been sufficient, Hilary knelt down before the wardrobe, and putting her hand to the back of the drawer, pulled out Margaret's morocco dressing-bag. It was the work of a moment only to fit the key in the lock, and then its contents were at the mercy of her prying eyes. But beyond the leather-covered case that Margaret had shown to Eleanor in the train the bag was empty, and Hilary, who had expected to find it crammed full of jewellery, experienced a sharp pang of disappointment. But when she opened the case and saw the pearl-studded locket and the beautiful row of pearls that formed its chain, her face brightened. The initials "M. A." on the back of the locket, to say nothing of the fine, copper-plate inscription, "For my daughter Margaret," that ran round the narrow gold setting of the miniature, were, of course, conclusive proof that it did not belong to Miss Carson. Hilary remembered, too, the handkerchief embroidered with those same incriminating initials which Miss Carson had one day dropped in the garden. Though it seemed to Hilary an unimportant matter now, she yet looked upon it as a link in the long chain of circumstantial evidence which she alone and unaided had forged against Miss Carson. Really, she thought, she had a right to be proud of herself, for had she not shown more intelligence and acumen in the detection of the Seabourne burglaries than every police official in the town. How every one would admire her skill! Her portraits might possibly appear in the illustrated papers, and as for the local papers, they would, of course, print long accounts of the marvellous way in which, working quite alone, she had succeeded in unravelling the mystery that had baffled the whole of the Seabourne police.
And as Hilary sat there pluming herself on her cleverness and lost in the pleasant dreams of the fame that would be shortly hers, the door opened, and Margaret, who had only just come back and was still in her outdoor things, walked into her bedroom.
It was not until she had advanced some way into the room that she saw Hilary, and then Margaret came to a sudden halt in sheer amazement at the scene that greeted her. Her astonished gaze travelled from Hilary round her room, with its disordered aspect, its open cupboards and ransacked drawers, and then she looked again at Hilary, who, with the open morocco case in her hand, met her eyes defiantly.
"Will you tell me, please, what you mean by this conduct, Hilary?" she said, feeling almost too amazed to be angry.
"Oh yes, I will tell you fast enough," Hilary said, who had been as taken aback by Margaret's sudden entry as the latter had been to find her there, and who, considerably to her own surprise and annoyance, was conscious of a distinct feeling of shame at the position in which she had been caught. But as she scrambled to her feet and faced Margaret she shook off that feeling. After all, it was for the latter to feel ashamed, not for her.
"You are found out," she said slowly and emphatically. "I have found you out."
"So," Margaret thought then, "it had come at last. Hilary, poking among her possessions, had somehow discovered her real name. Oh, poor Eleanor! What would happen to her now?"
"You ask me what I mean by coming into your room; but that's nothing. It is for you to explain how you dared to come into our house, a thief and a burglar like you. But I," throwing out her arm dramatically, "have unmasked you."
If Hilary had not been too excited by the vigour of her own denunciation to notice Margaret's expression, she might have been bewildered by the look of very decided relief which succeeded to the one of startled dismay with which Margaret had listened to the beginning of her speech. What Hilary had discovered, or fancied she had discovered, really did not matter as long as her secret and Eleanor's was safe.