LIGHTNING AND THUNDER 131 



that originally all the river channels of the earth 

 were ploughed by lightning. 



Lightning is a common accompaniment of sum- 

 mer rains, and repeated lightning strokes may be 

 the chief feature of a summer storm. Then again 

 there may be a rain without lightning or thunder 

 being seen or heard. Lightning is occasionally 

 noticed during early spring and late autumn, and 

 on rare occasions it makes startling appearances 

 during winter storms. 



Lightning seems to strike more frequently in the 

 plains and valleys than in the mountains. Dur- 

 ing three hundred and five climbs to the top of 

 Long's Peak I knew of lightning striking the sum- 

 mit but twice. Both bolts struck in precisely the 

 same spot, and in both cases the storm clouds were 

 high above the summit. 



Most rain storms in high mountains are on the 

 slopes, while the peaks and high plateaus tower 

 above in the sunshine. Sometimes the summit 

 points are in the midst of the storm, but being in 

 and not beneath the storm, they are therefore less 

 frequently struck than the slopes or the lowlands. 

 There may be exceptions in peaks of moderate 

 height or those highly mineralized. But when 

 storms cover the mountains the summits of peaks 

 rarely are below — in range of — thunder bolts. 



Peaks in the upper edge of the storm cloud are 

 frequently enveloped in what may be called an 

 invisible zone of electricity. This may ziz, ziz 



