74 



THE DESERT 



The river 



during 



floods. 



The "bore.' 



Meeting of 

 river and 

 sea. 



miles across, up to the very terraces of the 

 mesas, are covered ; and the red flood moves 

 like an ocean current, vast in width, ponderous 

 in weight, irresistible in strength. All things 

 that can be uprooted or wrenched away, move 

 with it. Nothing can check or stop it now. 

 It is the Grand Canyon river once more, free, 

 mighty, dangerous even in its death-throes. 



And now at the full and the change of the 

 moon, when the Gulf waters come in like a 

 tidal wave, and the waters of the north meet 

 the waters of the south, there is a mighty con- 

 flict of opposing forces. The famous "bore" 

 of the river-mouth is the result. When the 

 forces first meet there is a slow push-up of the 

 water which rises in the shape of a ridge or 

 wedge. The sea-water gradually proves itself 

 the greater and the stronger body, and the ridge 

 breaks into a crest and pitches forward with a 

 roar. The undercut of the river sweeps away 

 the footing of the tide, so to speak, and flings 

 the top of the wave violently forward. The red 

 river rushes under, the blue tide rushes over. 

 There is the flash and dash of parti-colored 

 foam on the crests, the flinging of jets of spray 

 high in air, the long roll of waves breaking not 

 upon a beach, but upon the back of the river, 



