NOME II. VESICULAR LAVA. 341 



alone can enable him to form ideas at all ade- 

 quate to objects so grand and astonishing. 



" The upper edges of the crater, to judge by 

 the eye, are about a mile and a half in circuit, 

 and form an oval, the longest diameter of which 

 extends from east to west. As they are in seve- 

 ral places broken, and crumbled away in large 

 fragments, they appear as it were indented, and 

 these indentations are a kind of enormous steps, 

 formed of projecting lavas and scoriae. The in- 

 ternal sides of the cavern, or crater, are inclined 

 in different angles in different places. To the 

 west their declivity is slight; they are more 

 steep to the north; still more so to the east; 

 and to the south-east, on which side I was, they 

 are almost perpendicular. Notwithstanding this 

 irregularity, however, they form a kind of fun- 

 nel, large at the top and narrow at the bottom, 

 as we usually observe in other craters. The 

 sides appear irregularly rugged, arid abound 

 with concretions of an orange colour, which at 

 first I took for sulphur, but afterwards found to 

 be the muriate of ammoniac, having been able 

 to gather some pieces of it from the edges of the 

 gulf. The bottom is nearly a horizontal plane, 

 about two-thirds of a mile in circumference. It 

 appears striped with yellow, probably from the 

 above mentioned salt. In this plane, from the 



