According to the Research Guide “Bankrupts and Insolvent Debtors:1710-1869” on the website of The National Archives (UK):
Until 1841, the legal status of being a bankrupt was confined to traders owing more than 100 pounds (reduced to 50 pounds in 1842). Debtors who were not traders did not qualify to become bankrupt, but stayed as insolvent debtors. Responsible for their debts but unable to pay them, they remained subject to common law proceedings and indefinite imprisonment, if their creditors so wished. … Insolvent debtors were held in local prisons, and often spent the rest of their lives there: imprisonment for debt did not stop until 1869.
Another ancestor of mine, Abraham WOOLF was imprisoned in the Debtors Prison, as this entry from the London Gazette of 1841 shows:
Shortly afterwards he came to trial, and fortunately his petition for release was granted. The following entry in the London Gazette gives more background about him – that he was currently a “General Dealer and Cigar Maker” and formerly a “Cigar Dealer and Ladies’ Shoe Maker”, as well as recent addresses:
In the documents at the National Archives in Kew, London, I could follow the progress of his imprisonment, petitions and release, however even the information available online on websites like The National Archives (UK) and The London Gazette tell me more about the life of this ancestor.