The calm of London’s local-studies libraries is often punctured by a sigh, the sound of an elderly lady finding out that the gentleman at the head of her family tree was a manservant.

More potent surprises are in the offing: the online archive of Old Bailey trials yields not only details of the crime, but also frequently the scene of the arrest and what the officer said as he apprehended a dastardly ancestor.

Descendants of George White, 18, who stood trial in 1873, can read of how the detective inspector exclaimed: “I am surprised at your being mixed up in these swindling transactions after the good advice I gave you when I apprehended your father.”

Looking for my own family name, I discovered that Philip Pavia, a tobacconist of High Holborn, appeared at the Old Bailey in 1843 as a victim of theft.

A man who may be the same Mr Pavia was walloped over the head ten times with a table leg in the early hours of a February morning in 1873. His housekeeper, Sarah Jones, found him in the parlour. “He was covered with blood, like a slaughtered bullock; he said the man in the kitchen had murdered him,” she reported.

The accused were his tenants, a father and son, and another man who had confided in Miss Jones that “the old man” Mr Pavia would “not live long”. The same Miss Jones was back in the Old Bailey the same year, accused of stealing 18 Russian bonds from the late Mr Pavia, who died on March 24 of that year.

Despite being brought up on tales of Pavias escaping certain death fleeing Italy by night and diamond merchants who died on foreign fields, most of my descendants in the late 19th century seem to have stayed on the right side of the law. The last Pavia to arrive at the Old Bailey was Felix Pavia, my great-great-grandfather, in 1906. He had been robbed.

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