Yes, Mallory did use O2 on Everest in 1924, and probably chose Sandy Irvine to go with him because Irvine knew more about how to maintain the O2 apparati than did Noel "I saw them above the second step going strong for the summit" Odell. This is the same Odell for which the gully in Huntington Ravine is named.
If Fritz Wiessner had made the summit of K2 in 1939, as he came really close to doing without O2, probably Hillary would not have taken O2 to Everest in 1953. Even in 1953 the O2 tanks and apparati were still very heavy and cumbersome, which required hundreds of porters and sherpas to get the extra weight to the South Col. Although O2 tanks and apparati are much lighter weight today, dozens of extra porters and sherpas are still required to get the extra weight to the South Col on commercial expeditions, which is the main reason that these expeditions are so expensive for clients. Of course, short-roping clients from the South Col to the summit does not come cheaply either.
Reinhold Messner and Peter Habeler were indeed first to summit Everest without O2, in 1979 I think. But, many of the other 11 who have done all 14 8000 meter peaks along with Messner summited Everest without O2, I believe. Messner and Habeler both wrote books about their O2-less ascent, which led to their falling out, because Messner was mad at Habeler who published his book first. Nevertheless, at the time Messner credited Habeler with the longest and fastest glissade in history from the South Summit to the South Col. Habeler wrote that he was in a hurry to get down because he had convinced himself that he was losing all of his brain cells from lack of O2.
Besides Ed Viesturs, there are five others still alive who have climbed 13 of the 14 8000 meter summits. I am not sure if any of the other five are on their 14th summit attempt this season. There are three more with 12, one with 11, and six with 10 of the 8000 meter summits to their credit. Three died with 10 or more completed.
Anatoli Boukreev died on Annapurna because he was caught in an avalanche, not because he was not using O2, which he never used on Everest either. Boukreev never got up 10 of the 8000 meter summits. Annapurna is the most dangerous 8000 peak, based on the ratio of fatalities to successful summit ascents.
If Fritz Wiessner had made the summit of K2 in 1939, as he came really close to doing without O2, probably Hillary would not have taken O2 to Everest in 1953. Even in 1953 the O2 tanks and apparati were still very heavy and cumbersome, which required hundreds of porters and sherpas to get the extra weight to the South Col. Although O2 tanks and apparati are much lighter weight today, dozens of extra porters and sherpas are still required to get the extra weight to the South Col on commercial expeditions, which is the main reason that these expeditions are so expensive for clients. Of course, short-roping clients from the South Col to the summit does not come cheaply either.
Reinhold Messner and Peter Habeler were indeed first to summit Everest without O2, in 1979 I think. But, many of the other 11 who have done all 14 8000 meter peaks along with Messner summited Everest without O2, I believe. Messner and Habeler both wrote books about their O2-less ascent, which led to their falling out, because Messner was mad at Habeler who published his book first. Nevertheless, at the time Messner credited Habeler with the longest and fastest glissade in history from the South Summit to the South Col. Habeler wrote that he was in a hurry to get down because he had convinced himself that he was losing all of his brain cells from lack of O2.
Besides Ed Viesturs, there are five others still alive who have climbed 13 of the 14 8000 meter summits. I am not sure if any of the other five are on their 14th summit attempt this season. There are three more with 12, one with 11, and six with 10 of the 8000 meter summits to their credit. Three died with 10 or more completed.
Anatoli Boukreev died on Annapurna because he was caught in an avalanche, not because he was not using O2, which he never used on Everest either. Boukreev never got up 10 of the 8000 meter summits. Annapurna is the most dangerous 8000 peak, based on the ratio of fatalities to successful summit ascents.
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