XV PAULINE'S PURCHASE Alone, Fleming Stone wrestled with the problem of the giving of that poison. The library at Garden Steps had been turned over to him for a study and no one entered the room unless summoned. Stone sat at the mahogany table-desk, but his eyes rested unseeingly on the beautiful fittings of polished silver and glass. On a memorandum block he wrote down the names of possible and probable suspects. To be sure, he thought, every one in the house might be deemed possible, as well as some who were not in the house. But each one must be taken into consideration. To begin with the most important, Miss Stuart. It was possible that she poisoned her aunt, but so improbable as to make it exceedingly unlikely. True, she was heir to half the fortune, but well-bred, well-nurtured young women do not commit crime to inherit their money sooner. Except for that conversation reported by Anita Frayne, there was not a shred of evidence against Miss Stuart. And Stone did not place implicit confidence in that story of the talk behind closed doors. He had discovered that the two girls were not friendly and he knew Anita capable of making up or coloring a tale to suit herself. Pauline had told him that she was in the hall-window-seat at one o'clock that night and had seen Anita coming from Miss Carrington's room. Or, to put it more carefully, she had seen her with her hand on the door-knob, in the act of closing the door after her. This Pauline had told to Stone, with an air of such verity and truthfulness that he was fain to believe her. However, in all honesty, he had to admit to himself, that Miss Stuart _could_ have given the poison in some secret way, had she so desired. The same was true, though, of Miss Frayne, of Haviland and of the various house-servants. But where could any of them get it? Again there were the Count and Mrs. Frothingham to be considered. In fact, there were too many suspects to decide among, without further evidence. "Any luck?" Stone asked of Hardy, who came in to report. "No, Mr. Stone. I've raked the drug shops thoroughly, and there's no trace of a sale of aconitine. It's practically impossible to buy such a substance. I mean, for the ordinary customer." "Yet somebody did." "I suppose so. But doesn't it limit the field of search to realize that it couldn't have been a servant or either of the young ladies?" "Why neither of the young ladies?" "But how could they get it?" "Why not as well as any one else? And somebody did." "Then somebody stole it. Nobody bought it. I'm positive of that, now I've learned how impossible it is to make such a purchase. And how could those girls steal it?"