7ft tapeworms, sexual infections, tarantula bites - just another day for navy doctors of yesteryear

Seven-foot worms in the gut, giant spider bites and lightning strikes were just some of the dangers facing travellers on the high seas in the 19th century, medical archives reveal today.

Those on board Royal Navy ships - whether sailors, passengers or convicts bound for the colonies - were also prone to tropical fevers and sexually transmitted diseases, according to naval surgeons' journals written between 1793 and 1880.

As well as daily "sick lists", their handwritten notes and illustrations included in more than 1,000 newly catalogued files held at the National Archives at Kew bring to life the experiences of travelling all over the world from Britain and Ireland. One describes an encounter with Eskimos during a voyage of discovery on His Majesty's Griper in the Arctic in 1824, when the assistant surgeon William Leyson recounted how presents were left for the natives.

In exchange, sailors took "several walrus heads" and a woman's head from a grave, he wrote.

Convicts on board the Albion heading to the penal colony of Australia in 1828 showed an "animated eagerness" when they saw their future home, according to surgeon Thomas Logan, while on the Eliza a group of prisoners performed the play Rob Roy to entertain the officers.

The locks on the same ship later had to be picked after the second mate fell overboard and was lost at the sea with the keys in his hand.

Alcohol is often mentioned in the journals, sparking drunken accidents, fights and, occasionally, being used as a medicine.

Rum was often administered for all sorts of problems, including scorpion and tarantula bites, while brandy was also available by prescription.

Treatment options were limited, but the surgeons tried to take care of their patients and expressed pleasure when they looked likely to recover.

According to Dan Gilfoyle, diplomatic and colonial records specialist, the documents give an insight into approaches to medicine and healthcare from those at the "front line" of the medical profession.

He said the 19th century was a period when many aspects of medicine changed "radically" as developments were made in the study of the causation of disease, moving on from previous theories of climatic causes to understanding germs.

The rapid expansion of the Empire also brought travellers into contact with new and varied diseases, though they often took many with them too.

The Royal Navy medical officers' journals have been catalogued by the National Archives as part of a two-year project funded by a 96,000 grant from the Wellcome Trust.

Project manager Bruno Pappalardo, principal record specialist manager, said the documents were "full of stories" and "humanity" which shone through.By cataloguing the files, historians and people researching family history or other subjects can search them much more easily, he added.

"The journals are the most significant source for the study of the history of health at sea for the 19th century," he said.