Scotland’s People has released details of inmates held at Ayr and Inveraray jails, offering insight into criminal lives in the 19th and early 20th centuries.

Among the most striking cases is that of American James Edward Lyon and Eliza Thorpe, who in the summer of 1883 targeted wealthy hotel guests from Argyll to Aberdeenshire. Cash and jewellery disappeared wherever they stayed, with suspicion repeatedly falling on the pair, who travelled as husband and wife.

They were eventually arrested at a hotel in Edinburgh, while an associate, Joseph Dowling, was caught with stolen items. Lyon and Dowling were convicted, though the case against Thorpe, then 20, was found not proven. Lyon was jailed for seven years.

Their images were preserved in a procurator fiscal’s album of notable cases, and their prison entries now form part of 4,600 Inveraray records newly digitised. The jail once held inmates of all ages, from seven-year-old James McCulloch, convicted of theft, to 82-year-old Ann Kerr, found guilty of “vagrancy”.

A further 98,000 records from Ayr prison, covering 1841 to 1911, have also been added. Among them are convicted murderers Joseph Calabrese, Thomas Bone and Mary Boyd, all sentenced to death but later reprieved.

Archivist Veronica Schreuder said: “Prison registers are a rich source of information for social researchers and family historians alike.

“While it can be a shock to find an ancestor in prison, it can sometimes lead to details that are unlikely to have been preserved for most people.

“Finding out the colour of their hair, details of their health or whether they could read or write can turn a name and some dates into a much more rounded person.

“And, of course, if they have committed a serious crime, it can explain a lot about the decisions of other relatives such as moving area, changing a name, or simply never talking about them.”

More than 400,000 historical prison records are now searchable on the site, including those from Edinburgh, Barlinnie, Perth and Largs.