FIELD AND STUDY 



upon it for half an hour. It was an unwelcome vis- 

 itor; but this morning the sun is working its magic 

 upon it and will leave no trace behind. In certain 

 conditions of the atmosphere the valley fog is slowly 

 burned up where it lies; at other times it ebbs and 

 flows, rises and sinks at intervals like the lava in a 

 crater. It comes up over the hills three or four 

 hundred feet above its night level, then withdraws, 

 then returns. It does this several times as if seeking 

 a way to escape. This ghost of a lake or river is as 

 uneasy when day comes as any other ghost, but by 

 or before ten o'clock it seems to pull itself together 

 and begins to rise upward in scattered flocks or 

 small clouds, reaching up to its kindred, the first 

 clouds that are passing over. It is precisely like a 

 flock of geese rising upward to join other flocks 

 that are calling down to them from above. 



The fog forms in the valley at night, just as water 

 would accumulate there if Noah's flood were to 

 come again, but not for the same reason, or under 

 the same law. The water seeks its level, and its 

 level is at the lowest point within reach. The level 

 of the fog is in the stratum of air where the clouds 

 float. Hence, after all, one may say the fog seeks its 

 level also, but it is up and not down. The fog is only 

 a finer rain. It is white because of the air it holds. 

 Its minute particles of water become little balloons 

 inflated with air; it would take thousands of them 

 to make one raindrop. Both rain and fog are the 

 298 



