Kangshungatse. A Netherlands expedition led by Jean François Sablet unsuccessfully tried to climb Kangshungatse or Makalu II (25,066 feet) by its south ridge. The highest point reached was 23,625 feet on October 11, the same day that Camp IV was established at 23,000 feet. Dr. Reyniesse and two others replaced those who had established Camp IV on October 14. That night they took sleeping pills. The other two woke up on the morning of October 16, having slept for 36 hours. They found Dr. Reyniesse frozen to death in the snow 500 feet below his tent. At what time, or why, he left his tent is not known. The dangers of taking sleeping pills at high altitudes are emphasized.
Michael Cheney, Himalayan Club