CHAP. XVII. FIFTH CA3IP ON CHIMBORAZO. 319 



barometer^ and^ found that the height (14,480 feet) was a little 

 above that of the Great Arenal. After crossing it we kept for 

 some time on a level/ and were then driven downwards to turn the 

 end of a large stream of lava.''^ Rounding the base of this, we came 

 upon an excellent place for camping, against a little rivulet, with 

 plenty of firing, and made there our fourth camp on Chimborazo 

 (14,359 feet). Min. temp, in night 30° Faht. 



The fourth cam^o was not high enough for a starting-point, and 

 on the 2nd of July we continued a few miles farther in a south- 

 westerly direction, and established the fifth camp at the height of 

 15,811 feet, against a very large block of lava ^ (apparently, a loose 

 mass imbedded in the soil, that had either been ejected or had 

 fallen from the cliifs above) a little to the north of the ridge which 

 hereafter will be termed the north-west ridge of Chimborazo.* I 

 identified this as the long ridge seen from G-uaranda, and knew 

 that it led directly towards the summit. Jean-Antoine, however, 

 maintained that I was mistaken. '^ I tell you what it is,^' said the 

 Chief of the Staff, "Monsieur deceives himself, j^rettily.'' 



* A few hundred yards on the west of the pass, the swampy soil suddenly gives 

 place to firm ground ; and a little farther on the sandy slopes commence which stretch 

 uninterruptedly round the north-west and western sides of the mountain. 



2 This prominent lava stream appeared to issue from the glaciers at the height of 

 about 18,000 feet, — one could not see precisely where, owing to the large quantity 

 of new-fallen snow. 



^ There was great difficulty in breaking specimens from this mass, which was 

 unlike any other rock that I saw on the mountain. When broken, it crumbled 

 somewhat in the manner of loaf-sugar. Prof. Bonney says: — "A rather crumbly 

 rock of very irregular fracture, having a very dark grey ground-mass, in which 

 crystals of glassy -white felspar, up to about '2 inch long, are imbedded. When 

 examined microscopically, it does not appear to differ materially from some of those 

 already described ... is different only in the colour of the ground-mass, and is best 

 named a hypersthene-andesite." — Proc. Royal Soc., June 19, 1884. 



^ The direction of this ridge is not strictly north - west. It is more nearly 

 north-north-west. 



