Himalayan Club Vice President Meher Mehta characterized Kellas' papers A Consideration of the Possibility of Ascending the Loftier Himalaya and A Consideration of the Possibility of Ascending Mt Everest as key catalysts in driving scientific thinking into climbing big peaks. His studies included the physiology of acclimatization in relationship to important variables like altitude, barometric pressures, alveolar PO2, arterial oxygen saturation, maximum oxygen consumption, and ascent rates at different altitudes. He had concluded that Mt Everest could be ascended by men of extreme physical and mental constitution without supplementary oxygen if the physical difficulties of the mountain were not too great.