CHAPTER XI 



THE BIVEB FLOODS 



THE Sierra rivers are flooded every spring by 

 the melting of the snow as regularly as the 

 famous old Nile. They begin to rise in May, and 

 in June high- water mark is reached. But because 

 the melting does not go on rapidly over all the 

 fountains, high and low, simultaneously, and the 

 melted snow is not reinforced at this time of year 

 by rain, the spring floods are seldom very violent 

 or destructive. The thousand falls, however, 

 and the cascades in the canons are then in full 

 bloom, and sing songs from one end of the range 

 to the other. Of course the snow on the lower 

 tributaries of the rivers is first melted, then that 

 on the higher fountains most exposed to sunshine, 

 and about a month later the cooler, shadowy 

 fountains send down their treasures, thus allowing 

 the main trunk streams nearly six weeks to get their 

 waters hurried through the foot-hills and across 

 the lowlands to the sea. Therefore very violent 

 spring floods are avoided, and will be as long as 

 the shading, restraining forests last. The rivers of 

 the north half of the range are still less subject 

 to sudden floods, because their upper fountains 

 in great part lie protected from the changes of 



258 



