Experiments on the Nervous System with Opium and Metalline Substances Made Chiefly with the View of Determining the Nature and Effects of Animal Electricity

"Experiments on the Nervous System with Opium and Metalline Substances" by Alexander Monro is a scientific exploration from the 1700s that investigates how opium and metals impact the nervous system, interpreting their effects through the concept of animal electricity. Monro shares a collection of experiments, primarily using animals like frogs, documenting their reactions to injected opium and applied metals, noting changes in convulsions, heart rate, and muscle activity. His findings reveal that opium generally causes paralysis and reduces muscle activity, whereas metals tend to induce convulsions. Monro uses these observations to argue that there are key differences between nervous energy and electricity, adding essential insights to the understanding of physiology and neurobiology.