The Adventure of the Cardboard Box

We may take it that the sender of the packet is the man whom we want. But he must have some strong reason for sending Miss Cushing this packet. What reason then? It must have been to tell her that the deed was done! or to pain her, perhaps. But in that case she knows who it is. Does she know? I doubt it. If she knew, why should she call the police in? She might have buried the ears, and no one would have been the wiser. That is what she would have done if she had wished to shield the criminal. But if she does not wish to shield him she would give his name. There is a tangle here which needs straightening to.” He had been talking in a high, quick voice, staring blankly up over the garden fence, but now he sprang briskly to his feet and walked towards the house.