A logbook from one of history's greatest boat journeys has helped researchers navigate its success.
Navigator Frank Worsley's navigation books from the Endurance expedition, including the book he used on the James Caird, are in Canterbury Museum's collection. Photo: Supplied / Canterbury Museum
International researchers had been investigating how the lifeboat James Caird made it across 1500km of sub-Antarctic sea in 1916.
The researchers replicated the logbook's calculations, which helped them understand what an impressive feat navigating the James Caird was.
A Canterbury Museum spokesperson said the voyage was undertaken by Sir Ernest Shackleton and his crew after their main ship was crushed by pack ice in October, 1915.
The spokesperson said the logbook belonged to James Caird's navigator, Akaroa-born Frank Worsley, and was part of an internationally significant collection at the museum.
Frank Worsley. Photo: Supplied / Canterbury Museum 1981.110.91
One of the researchers Robin Stuart said it was important Mr Worsley got his calculations correct.
"Worsley had to take the sights and manually perform the reduction calculations sitting on ballast rocks in a small boat heaving on ocean swells. Yet for that critical 14-day period we did not find a single error.
"That he was able to do this in the cold, damp and cramped conditions using rapidly disintegrating navigation books is remarkable indeed.
"Without Worsley's superlative skills as a navigator Shackleton's expedition might be remembered as a tragedy rather than the epic tale of Antarctic survival we know it as today."
The researchers' conclusions were published in volume 32 of Records of the Canterbury Museum, the museum's annual research publication.
Launching the James Caird from Elephant Island. Photo: Photo by Frank Hurley / Canterbury Museum 19XX.2.268