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The American Angler 



into Salmon River valley were, at their 

 lower ends, made thinner and thinner 

 by the heat of the sun's rays, and some- 

 where in the valley each reached a 

 point where the sun's heat was great 

 enough to melt the ice as it slowly crept 

 out from the canons. At the upper end 

 of each canon, high, rocky cliffs frowned 

 down upon the ice-river, and bold, 

 rocky walls hemmed it in on either 

 side. Rain and frost and the summer's 

 sun all conspired to destroy these cliffs 

 and walls of granite. The sun melted 

 the snow upon them, and into the 

 crevices and rifts ran the water, which 

 was the wedge, and then at night the 

 frost came and froze the water, which 

 was the same as hitting the wedge hard 

 blow after blow and driving it deeper 

 and deeper into the rock which was 

 strong ; but the freezing, expanding ice 

 was stronger ; and so little flakes and 



small chunks of granite, and even great 

 masses weighing hundreds, yes, thou- 

 sands of pounds, were split from the 

 parent rock and all went thundering 

 down upon the ice-river below. There 

 they lay and were carried slowly along 

 on the surface, or else, melting their 

 way to the bottom of the stream, as 

 many of them did, were there pushed 

 onward in the same irresistible way. 



In the course of years thousands of 

 tons of rock fragments thus reach the 

 glacier, as we know the river of ice to 

 be ; and those rocks which find their 

 way to the bottom of the stream, or lie 

 upon the margins, scrape and grind 

 against the caiion's floor and walls, 

 wearing down and planing off the ir- 

 regularities and inequalities in each. 

 Small irregularities are entirely worn 

 away and a smooth or finely-straited 

 surface is produced, while greater ones 





LAKE MEADE, ABOVE REDFisH LAKE, IDAHO. — About 9, GOO feet above sea level. 



