ASCENT FROM PUENTE INFERNILLO. 79 



but even more brilliant, than those of the common 

 garden species, climbed over the bushes. A fleshy- 

 leaved Oxalis, the first seen of a numerous group, 

 came out of the crevices of the adjoining rocks, and 

 Alonsoa acutifolia, which I had never seen but in an 

 English greenhouse, was an additional prize. 



Night had completely fallen as we resumed our 

 journey, and although my curiosity was much excited 

 in the attempt to follow the course of the line, I utterly 

 failed to do so. Watching the stars as guides to our 

 direction, where these were not cut off by the frequent 

 tunnels, I could only infer that we were constantly 

 winding round sharp curves, at times near the bottom 

 of a deep ravine, with the roar of a torrent close at 

 hand, and soon after working at a dizzy height along 

 the verge of a precipice, with the muffled bass of a 

 waterfall heard from out of the depths. Even after 

 I had travelled the reverse way in broad daylight, I 

 remained in some doubt as to the real structure of 

 this part of the line. So far as I know, the first 

 application of a spiral tunnel in railway construction 

 was on the line across the Apennine between Bologna 

 and Florence, but the spiral is there but a semicircle ; 

 you enter it facing north, and emerge in the opposite 

 direction at a higher level. A similar device has been 

 more freely resorted to in the construction of the 

 St. Gothard line ; but on this part of the Oroya line, 

 completed before that of the St. Gothard was com- 

 menced, the spiral, if I mistake not, includes two 

 complete circles, at the end of which the train stands 

 nearly vertically above the point from which it started. 

 It is by no means altogether a tunnel, as the form of 



