Chemist Harkup’s first book is the product of her passion for the work of Agatha Christie and her broad knowledge and research in the matter of poisons.
Christie was a volunteer nurse in a hospital dispensary in Torquay during World War I, a position that required she pass exams to qualify as a dispenser. In those days, prescriptions were made by hand, so she had a strong working knowledge of drugs and poisons. With the publication of her first novel, The Mysterious Affair at Styles (1920), Christie received one of her most cherished compliments when the Pharmaceutical Journal and Pharmacist praised the correctness of her writing. Harkup devotes each of 14 chapters to a particular poison (belladonna, cyanide, ricin, thallium, and others), and she explains each thoroughly, including its origins, how to extract it from the most potent part of the plant, and its benign uses (for humans) such as pesticides. Then the author explores the most effective ways of dosing, whether by injection, dissolved in food, tea, or inhalation, and the effects on victims. She also lists antidotes, if there are any. Post-mortem testing is a large part of determining if a murder has been committed, and Harkup lists tests available at the time the books were written (many are still in use). This would be a perfect reference for anyone writing murder mysteries and is scientific enough to be used as a textbook, which is also its only drawback. Technical explanations will daunt average readers with little knowledge of chemistry (the author also includes an appendix with drawings of each poison’s chemical structure), but the narrative is informative, and the author’s easy style of writing makes up for the slow bits.
The addition of real-life cases and comparisons to Christie’s works make this a nice little murder mystery of its own. Fear not, she’s careful not to spoil the endings of the classic novels.