Royal Navy Seaman Frederick Allen's 'ditty box' contains information not held by naval archives (Picture: Gardiner Houlgate).
Journals detailing the lives of Victorian sailors could fetch thousands of pounds at auction after being discovered at a flea market.
The three documents, handwritten by Royal Navy Seaman Frederick Allen, provide a day-to-day account of the Mediterranean voyage of HMS Australia from 1889 to 1893.
Some details are not found archives for the Mediterranean Dreadnought Project - when the Navy defended the sea link between Great Britain and countries forming the British Empire in the eastern hemisphere.
Seaman Allen, born in 1869, details capsizings, drownings, military engagements, several stabbings and seasickness.
The journals were discovered in Seaman Allen's ditty box, the name of a container for sailor's personal items, by a private collector at a flea market in Somerset.
The box also contains photographs, uniforms, Navy-issued handbooks and handwritten records, and will be sold at auction by Gardiner Houlgate in Corsham, Wiltshire, on 26 September.
David Hare, Director and Auctioneer at Gardiner Houlgate, says the journals will be the most "comprehensive and richly-detailed" maritime items they have ever sold.
"It's a rare piece of British naval history. On that basis, we're expecting it to sell for several thousand pounds." he said.
In the journal, Allen also writes about the alleged murder of one of his fellow crew members, William Drudge - found dead at the foot of a cliff in Greece in May 1891.
Seaman Allen built his own case against a Russian sailor and a Greek man, last seen with Drudge at a bar - prompting an investigation and further protest.
"It's real Boy's Own stuff but with a dark undercurrent of violence and death", says Mr Hare.
The auctioneers are calling for more information on the life of Frederick Allen, who is unknown outside of his naval service record. Mr Hare said:
"Beyond the story these journals tell of British maritime power at the height of the Empire.
"They also paint a vivid picture of the daily lives of sailors aboard ship - the dangers they faced, the camaraderie, the heroism."