He should have gotten rid of the chemist

The chemist had the incriminating Ledger, in which all listings of purchases for dangerous drugs and poisons had to be signed for. If anything happened to Blagdon, it would be in the hands of the police before Geoffrey Carroll was half way home.

They didn't specify the cause of the First Mrs. Carroll's Illness, but the symptoms are consistent with ARSENIC poisoning. A slow and reasonably quiet, wasting illness.

The nice thing about Arsenic, is that it hangs around. The first Mrs. Carroll would have been exhumed, Arsenic found... and that, combined with Sally's illness and Blagdon's Ledger, would have put Geoffrey in the noose.








"I do hope he won't upset Henry.."

I had similar thoughts. At that perfect moment in the story when the Chemist's safe was open he really should have set a fire after knocking the guy out. That would have done for the blackmailer AND the evidence.

Hindsight.

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