334 USPALLATA PASS. [chap. xv. 



The scenery thus far was very uninteresting, compared with 

 that of the Portillo pass. Little can be seen beyond the bare 

 walls of the one grand, flat -bottomed valley, which the road fol- 

 lows up to the highest crest. The valley and the huge rocky 

 mountains are extremely barren : during the two previous nights 

 the poor mules had absolutely nothing to eat, for excepting a few 

 low resinous bushes, scarcely a plant can be seen. In the course 

 of this day we crossed some of the worst passes in the Cordillera, 

 but their danger has been much exaggerated. I was told that if 

 I attempted to pass on foot, my head would turn giddy, and that 

 there was no room to dismount ; but I did not see a place where 

 any one might not have walked over backwards, or got off his 

 mule on either side. One of the bad passes, called las Animas 

 (the Souls), I had crossed, and did not find out till a day after- 

 wards, that it was one of the awful dangers. No doubt there are 

 many parts in which, if the mule should stumble, the rider would 

 be hurled down a great precipice; but of this there is little 

 chance. I dare say, in the spring, the " laderas," or roads, 

 which each year are formed anew across the piles of fallen 

 detritus, are very bad ; but from what I saw, I suspect the real 

 danger is nothing. With cargo-mules the case is rather different, 

 for the loads project so far, that the animals, occasionally running 

 against each other, or against a point of rock, lose their balance, 

 and are thrown down the precipices. In crossing the rivers I 

 can well believe that the difficulty may be very great : at this 

 season there was little trouble, but in the summer they must be 

 very hazardous. I can quite imagine, as Sir F. Head describes, 

 the different expressions of those who have passed the gulf, and 

 those who are passing. I never heard of any man being drowned, 

 but with loaded mules it frequently happens. The arriero tells 

 you to show your mule the best line, and then allow her to cross 

 as she likes : the cargo-mule takes a bad line, and is often lost. 



April 4th. From the Rio de las Vacas to the Puente del 

 Incas, half a day's journey. As there was pasture for the mules, 

 and geology for me, we bivouacked here for the night. When 

 one hears of a natural Bridge, one pictures to oneself some deep 

 and narrow ravine, across which a bold mass of rock has fallen ; 

 or a great arch hollowed out like the vault of a cavern. Instead 

 of this, the Incas Bridge consists of a crust of stratified shingle, 



