This Scottish radical and arsonist came to Plymouth in 1776 in an attempt to burn down the Dockyards in an act of sympathy with the American Revolutionaries. He had already started a small conflagration at the Portsmouth Dockyards a few weeks earlier. After failing to start any fires in Plymouth he moved on to Bristol where he had more luck. He was eventually captured and hanged on the mizzen mast of a Royal Naval ship in Portsmouth for his treachery. Arson in Her Majesty's Dockyards was given a specific law resulting in death that stayed on the statute books for many years. Plymouth's Dockyards kept a working execution chamber until relatively recently.
More information can be found in The Incendiary: John the Painter : The First Modern Terrorist by Jessica Warner
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