Had a great talk with a Dr. Anthony Karuza, who is a retired Dr. and mountaineer. We talked about his climb up Aconcagua 1976 (23,000 ft:highest peak in world outside of central Asia), Mt McKinley: rarely climbed Cassin Ridge (open bivouac at 12,000 feet, fell 100 ft next day). Everest: 3 1/2 months in Tibet, up to 25,000 ft.and the North face Mt Rainier: last to climb it in 1989. Survived only because of the "call of nature"!