Salmon skin bags and a seal intestine raincoat: How 19th century Arctic treasures are being brought back to life

UK scientists, tasked with bringing Arctic treasures back to life, have been getting to grips with a decidedly fishy story.

In one of the British Museum's most challenging science-based operations, specialist staff have had to develop ways of conserving a collection of artefacts made of fish skin, walrus intestines and other highly unusual marine-originating materials.

It's the first time in British conservation history that scientists have faced such a task.

In preparation for the British Museum's first ever comprehensive exhibition on the Arctic (opening to the public this Thursday), scientists had to prepare the rare artefacts for public display.

Two extraordinary bags, made by native Alaskans out of salmon skin in the 1880s, will be among a range of other highly unusual items in what will be a unique exhibition.

The museum's scientists have had to find ways of conserving not only fish skin, but also artefacts made of walrus intestines, ducks' feet, seal bladder, tree bark, reindeer muscle tendons and 150-year-old grass.

Never before have UK conservation scientists been faced with having to conserve such a wide range of marine-derived and other unusual materials.

To conserve and repair the two 130-year-old fish-skin bags, British Museum conservators had to temporarily recreate their original flexibility by enveloping them with water vapour for 24 hours inside a special polythene tent in their laboratory.

Rejuvenating the two artefacts had to be done very gently and slowly because of the complex way in which the 19th century Arctic artisans had made them.

Ethnographic research into Arctic fish-skin technology revealed that the 23 salmon skins used to make the two bags had first been scraped to remove all traces of fat and flesh. They had then been tanned with human urine before being treated with fish or seal oil. In order to learn precisely how the process worked, one of the British Museum conservators involved in the conservation operation, Sophie Rowe, went to Scandinavia to be taught by a traditional tanner how to turn fish-skins into leather.

The 19th century artisans – from the Yupik people of South West Alaska – had then used fish bone needles and reindeer or caribou muscle sinew to sow the scraped, tanned and treated salmon skins together.

The manufacturing process had then been completed by dying the tanned salmon skins red (possibly with red alder bark) and by adorning them with strips of white seal-throat collagen and caribou chin hair.

The larger of the two bags measures 80 x 60 cm and was probably used to store and carry clothes. It seems to have been remarkably robust. The small one – 50 by 40 centimetres – is believed to have been used to collect and carry berries and other food.

Another artefact that posed a challenge to the museum's conservators was a 90-year-old hooded ‘raincoat’, made of walrus or seal intestines, by artisans on Alaska's Aleutian Islands.

To conserve it, and repair a number of tears, the British Museum conservation scientists had to use ultra-thin translucent nano-cellulose. Usually that material (made of highly processed plant material) is used to repair ancient and other parchment manuscripts – so it was the first time in conservation history that it had been employed to rejuvenate artefacts made of animal intestines. To make the task even more complex, the raincoat was decorated with salmon skin square and triangular patches.

Another artefact made of walrus or seal intestines was the 110 year old sail of a large roughly eight metre long open Arctic skin boat known as an umiak.

To turn the animal's intestines into a sail or the equivalent of a waterproof jacket, the Arctic artisans had to use their mouths to blow them up like balloons.

After being left to dry in the Arctic wind for several weeks, they were then cut into long strips and finally sewn together with seal or walrus muscle sinew.

Other conservation challenges for the exhibition included a bag made from the skin of a duck's foot, a massive seal-shaped float - made of sealskin and used for hunting them - and a complete sealskin kayak from the Aleutian Islands, off North West Alaska.

Other rare artefacts in the exhibition include a float - from a wood and bone harpoon - made from a seal or walrus bladder, a pair of socks made from woven Arctic tundra grass and an ivory harpoon made of narwhal tusk. For centuries such tusks were believed by European ivory artisans and consumers to be the horns of unicorns.

Two of the finest objects in the exhibition are a pair of embroidered reindeer skin boots, acquired by Captain Cook, or one of his senior colleagues, during Cook's voyage to Alaska in 1778.

It's the first time any museum in the UK has conserved and displayed such a wide range of extraordinary Arctic artefacts.

They represent the cultures of more than forty different native Alaskan, Inuit, Siberian, Sami (northern Scandinavian) and other Arctic and subarctic peoples who skilfully used to the full (and in many cases still use) the relatively scant resources available to them, to make extremely durable, effective and beautiful artefacts for their daily lives.

The exhibition, Arctic: Culture and Climate, opens this Thursday and is being sponsored by Citigroup Inc – the New-York-based investment bank and financial services corporation. As well, as funding the Arctic exhibition, it is also the latest major bank to stop investing in Arctic oil and gas projects.

One of the conservation scientists who brought the museum's Arctic treasures back to life, Sophie Rowe, regards the exhibition's artefacts, and the materials used to make them, as “testimony to the amazing ingenuity of the communities in the circumpolar regions.”

“The people who live in these harsh environments have a respectful relationship with the resources and animals around them. The drive to ensure no part of a slaughtered animal is wasted means that parts of animals that we would usually discard have been beautifully and expertly crafted into the most wonderful materials and objects,” she said.