@jnicholes, I found the story buried in a Wikipedia article. I copied the story. Here it is:
An early 19th-century legend set in England also details the account of a clock striking thirteen at midnight and saving a man's life. The clock in the tower of
St. Andrews Church in
Plymouth is said to have mysteriously struck thirteen on a night when two strangers stood under it, one of whom was Captain Jarvis. They both remarked about how strange it was. Weeks later, the other man was put on trial in
Bodmin for having committed a murder on that night, and, not knowing even the name of the stranger who had witnessed the clock striking thirteen with him, had no alibi by which to clear himself. Just prior to being
sentenced as guilty of the murder, on the closing day of the trial, the judge asked him if he had any last words. He replied saying he had nothing to say except that he was innocent, and only one man in the world, whom he did not know, could clear him, for they two had both heard the clock of
St. Andrews Church in
Plymouth strike thirteen on that night in question. As he gave this testimony, Captain Jarvis, who had just arrived, called out that he was the man, and that the one on trial was innocent--after which he related his own miraculous turn of events that had brought him to the trial of this stranger, including riding a horse, not knowing where he went, which seemed guided to the very place of the trial. As he was known by a number of those present in the court, Captain Jarvis' words were accepted without question, and the innocent man was set free.
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