The 1921 Everest reconnaissance expedition was funded by the Royal Geographical Society, the Alpine Club and the Survey of India with a remit to explore the approaches to Mount Everest from Sikkim and through Tibet, and to investigate possible routes for climbing the mountain. Reaching the summit was not a primary objective. For geographical survey work the Survey of India appointed its own officers and the Geological Survey of India appointed Heron to conduct a widespread geological survey and to produce a map. Charles Howard-Bury led the expedition. Harold Raeburn and Alexander Kellas were to lead the climbing team but, after Kellas' sudden death on the walk-in, and Raeburn's illness requiring him to return to base, George Mallory effectively became lead climber. Henry Morshead led the survey work.