CORA SHEAR-TAIL HUMMING BIRD. 87 



Another disease often met with is bhnd- 

 ness. The brilhance of the sun on the 

 dazzHng white of the snow has that ejQfect ; 

 and the utmost caution is necessary to 

 protect the eyes from the excessive glare. 



Now and then the traveller is overtaken 

 by a terrific storm of thunder and light- 

 ning. For hours the flashes continue with 

 awful brilliancy, and the white snow looks 

 as if tinged with blood. 



The traveller is obliged to abandon his 

 mule, and creep under the shelter of some 

 rock or cave until the storm is over. 



And here, too, in his journey over this 

 wild part of the country, he comes upon 

 those wonderful bridges that look like 

 mere threads over an abyss. 



The bridge is, in fact, merely a thick 

 strip of hide or undressed leather that is 

 fixed from one side of the torrent to the 

 other. 



