Mallory and Irvine Research Expedition

The goal of the Mallory and Irvine Research Expedition of 1999 was to discover evidence of whether George Mallory and Andrew Irvine had been the first to summit Mount Everest in their attempt of 8–9 June 1924. The expedition was organized by regular Everest expedition leader Eric Simonson and advised by researcher Jochen Hemmleb, with a team of climbers from the U.S., the United Kingdom, and Germany. Hemmleb's investigations of sketchy reports of earlier sightings and photographs had led him to identify what he believed was the area in which Irvine's body lay, some distance below where his ice axe had been found by Percy Wyn-Harris on the expedition led by Hugh Ruttledge in 1933. The team hoped in particular to find a camera on Irvine's body which, had the pair been successful, should have contained a picture of the summit. Within hours of commencing the search on 1 May 1999, Conrad Anker found a body on the North Face, at 8,155 m; but to their surprise it was that of Mallory, not Irvine.

Mallory lay face-down, arms outstretched as if to break a sliding fall, with one broken leg and a serious wound to the skull, but otherwise very well-preserved. It seemed probable that he had been a victim of a fall while roped to Irvine. The body was only an hour or two from the safety of their camp.

Many artefacts were found on the body, including a pocket knife, altimeter, and snow-goggles, but no camera. Three discoveries in particular fuel continuing speculation:

The expedition interred Mallory where he lay.

During a second expedition in 2001, the team abandoned their search for Irvine to rescue several other climbing parties stranded on the mountain and in deep distress. The victims included two Chinese glaciologists, three Russian climbers, an American guide, and his Guatemalan client. Several of the climbers were suffering from high altitude cerebral oedema, a condition where the victim can hallucinate, lose balance and eventually the ability to even walk, due to lack of oxygen (which, high up on Everest, is only one-third the partial pressure of oxygen at sea level) in the brain. This condition has led to many deaths and injuries in mountaineering.

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