A drop of liquid falls from the sky in the shape of a snowflake. It can travel great distances, from the Atlantic Ocean to the peaks of the Alps and back to the sea via the Danube, the Rhone, the Po or even the Rhine. Its wandering lasts from a few hours to half a century. It all depends on the winds. Then it reaches the ground. Its needles become rounder and eventually disappear. The flake becomes an ice crystal. It merges with other flakes that do the same. A névé is formed. The crystals agglomerate again and become a glacier. In this way the snow piles up into compact ice on the slopes of the Bossons glacier in the Chamonix Valley. Then the crystals melt and the flake returns to its original condition as a drop of water: ‘Describing a glacier means telling the story of this journey.’

(Thinking Like an Iceberg, pp. 29-30)