By Virginia Phillips
BBC Science staff
When mountaineer Graham Hoyland returns to Mount Everest next year, he will not be clad in modern hi-tech fibres with tog ratings and windchill factor reduction.
The mystery of Mallory and Irvine's expedition has endured (Photo: John Noel Photographic Collection)
Instead, he'll be sporting replicas of garments last taken to the Himalayas in 1924, on the ill-fated expedition of George Mallory and Andrew (Sandy) Irvine which left both pioneers dead.
Whether they reached the summit before succumbing to Everest's harsh conditions is unclear.
They have acquired a reputation for a somewhat amateurish approach, based in part on photographs taken at base camp showing them wearing the English gentleman's attire of plus fours and tweed jackets.
Hoyland is a great nephew of another of the expedition's members, and six years ago was one of the team which discovered Mallory's final resting place.
"When we found his body it was a mixture of horror and amazement," he told the BBC's Science in Action programme.
Mallory's jacket would have kept out the cold Himalayan winds
So why would Hoyland, a seven-time Everest veteran, even be contemplating going back to the mountain with the same designs and fabrics?
Part of the answer is that Mallory and Irvine swapped their plus fours for much more appropriate attire when they began their ascent.
"Even when we found the body," said Graham Hoyland, "it was obvious that he had layer upon layer of thin garments, although the clothes were in tatters."
The layers were of silk, cotton and wool, alternating beneath an outer covering of tough gabardine.
"The typical myth of Mallory was that he was under-equipped and amateurish," said Mary Rose, Professor of Entrepreneurship at Lancaster University in the UK, who was inspired by the discovery of Mallory's body to attempt a recreation of his wardrobe.
In fact, she said: "We've found that he understood his clothing probably better than modern climbers.
"It was quite an advanced system; the silk gave wind-proofing, and the silk and woollen layers moved off each other so it was quite easy to climb."
Reconstructing the past
Professor Rose worked closely with outdoor clothing manufacturers and researchers at other institutions.
Vanessa Anderson, a performance sportswear masters student from the University of Derby, recreated several items including Mallory's cotton leggings.
"It's a knitted fabric using a tuck stitch which gives a 3d structure - similar to a honeycomb effect," she said.
"It's ideal for trapping air next to the skin, giving better insulation."
From historical documents and the remains of Mallory's cotton leggings, Vanessa researched sewing patterns to recreate the garment.
She has also reconstructed the gabardine jacket which Mallory wore. It was initially developed as a shooting jacket, with a 'pivot sleeve', allowing arm movement over the head without exposing the midriff to a nasty chill; perfect for mountaineering.
The researchers have also found that Mallory's apparel weighed much less than modern equivalents.
This, said Mary Rose, has inspired outdoor clothing manufacturers to reconsider the role of natural fibres; though the reconstructed clothes need to be tested in Himalayan conditions.
The next step is to test the rebuilt garments on Everest itself
"If you simply simulate you won't understand the tacit knowledge behind the clothing," she said.
"Actually testing it in the field gets you a real sense of how the clothing performs."
This is what Graham Hoyland hopes to discover when he tries it out on Everest next year.
"I guess I will find it much easier to move across the terrain, but I imagine the wind will be really cutting," he said.
"I think Mallory and Irvine did actually climb the mountain in 1924, and certainly there's nothing in this clothing to suggest they didn't."