Mallory and Irvine are seen here carrying only two cylinders, but each climber would need three cylinders apiece, or 25 pounds of weight, to have the slow oxygen flow of two liters a minute for the 12-hour summit attempt. With such a slow rate and such a heavy load, it is arguable whether the oxygen really helped them. Today, two liters per minute is considered the "break even" point for carrying a lighter, 15-pound oxygen unit. At this rate, climbers expend almost more energy carrying the load than they receive from their supplemental oxygen.

See Mountain Gear: Now
Back to High Exposure

Support provided by

For new content
visit the redesigned
NOVA site