As a kid, I loved detective stories. My favorites were Agatha Christie (I can’t wait to read this new bookabout poisons in Agatha Christie stories). I also devoured Sir Arthur Conan Doyle’s Sherlock Holmes stories. Both Christie and Conan Doyle were not just excellent writers—they were both excellent chemists. It was their stories that sparked my lifelong fascination with poison.

So I was thrilled to discover this award-winning articleat the Baker Street Journal website written by Harold Billings. While a librarian at the University of Texas, Austin, Billings acquired a medical textbook called The Essentials of Materia Medica and Therapeutics, written by Sir Alfred Baring Garrod. The copy is signed Arthur Conan Doyle/Edinburgh University/1878–79.

Conan Doyle was a doctor. He got his medical degree from the University of Edinburgh in 1881. Virtually every page of the book is heavily underlined and annotated in Doyle’s hand.

In one of his margin notes, Conan Doyle describes the effects of arsenic poisoning. Billings points out that it’s written with strange line breaks and punctuated as though in verse. (Conan Doyle does this with other poisons throughout the book.) He conjectures that the verse form may simply have been Conan Doyle amusing himself, or perhaps that he was writing it as a mnemonic device so that he could remember the symptoms. Whatever the reason, it’s one of the most evocative descriptions of the symptoms of arsenic poisoning I’ve seen.

Slow Arsenic Poisoning Vomiting—plenty of stools
Pain in the stomach & bowels
Pulse Wiry. Forehead feels stuffy
Eyes are red and are puffy,
The Last of the symptoms may seem a, Slight one, and that is eczema.
–ACD.

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