Glacial afterthought

A few centuries after a snow crystal melted on a Swiss glacier and joined other drops of water to run down the mountainside, carrying slivers and chips of rocks with them, they tumbled into the Rhone River. From there they rushed along to Lake Geneva, with the idea of getting down to the south of France and the Mediterranean. Many of them made it. Other bits of water and glacial sediment were sidetracked by the beauty of the shores of Lake Geneva. There they sit today. Every now and again the spotlight in on them. This happens mainly on days when the sun shines then black clouds arrive and winds blow. The lake shifts from blue to black to a strange glacial green.