Alfred Porter Southwick (1826–1898) was a steam-boat engineer, dentist and inventor from Buffalo, New York. He is credited with inventing the electric chair as a method of legal execution.

In 1881, Alfred Southwick conceived the idea of electrical execution when he heard the story of an intoxicated man who touched a live electric generator. Given that the man died so quickly, Southwick concluded that electricity could be used as an alternative to hanging for executions. His first application for this phenomenon was to help invent a way to euthanize stray dogs at the Buffalo SPCA but within a year he was publishing his ideas on using this method for capital punishment in scientific journals. As Southwick was a dentist who was accustomed to performing procedures on subjects in chairs, his device for electrical execution appeared in the form of an "electric chair."

On August 6, 1890, William Kemmler was executed by electrocution. Southwick was present and is reported to have said "There is the culmination of ten years work and study! We live in a higher civilization from this day."

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