FLOODS IN SWITZERLAND. 135 



this sort. Or rather, perhaps, we should draw a dis- 

 tinction between the two divisions of Switzerland 

 referred to above. Of these the one may be termed 

 the mountain half, and the other the lake half of the 

 country. It is the former portion of the country which 

 is principally subject to the dynamical action of water. 

 A long-continued and heavy rainfall over the higher 

 lands cannot fail to produce a variety of remarkable 

 effects, where the arrangement of mountains and passes, 

 hills, valleys, and ravines is so complicated. There are 

 places where a large volume of water can accumulate 

 until the barriers which have opposed its passage to the 

 plains burst under its increasing weight; and then 

 follow those destructive rushes of water which sweep 

 away whole villages at once. It is, in fact, the capacity 

 of the Swiss mountain region for damming up water, 

 far more than any other circumstance, which renders 

 the Swiss floods so destructive. 



And then it must be remembered that there are at 

 all times suspended over the plains and valleys which 

 lie beneath the Alpine ranges enormous masses of 

 water in the form of snow and ice. Although in gene- 

 ral these suffer no changes but those due to the partial 

 melting which takes place in summer, and the renewed 

 accumulation which takes place in winter, yet when 

 heavy rains fall upon the less elevated portions of the 

 Alpine snow, they not only melt that snow much more 

 rapidly than the summer sun would do, but they wash 

 down large masses, which add largely to the destructive 

 power of the descending waters. 



