From the archive record
An avalanche down a steep couloir or rocky ravine running over a cliff, in the Himalaya, as seen in the upper reaches of Himachal Pradesh, India. According to Wikipedia: "An avalanche is a sudden, drastic flow of snow down a slope, occurring when either natural triggers, such as loading from new snow or rain, or artifical triggers, such as snowmobilers, explosives or backcountry skiers, overload the snowpack. The influence of gravity on the accumulated weight of newly fallen uncompacted snow or on thawing older snow leads to avalanches which may be triggered by earthquakes, gunshots and the movements of animals. Avalanches are most common during winter or spring but glacier movements may cause ice avalanches during summer. Avalanches cause loss of life and can destroy settlements, roads, r