ADIORAT SANDSTONES. 171 



cliffs of it which form the head of the Haddas and 

 Komayli ravines, and which surround valleys such as 

 Baragit and Guna Guna, south of Senafd, appear as if 

 cut out of a huge unstratified block. 



In thickness the sandstone varies ; and as the original 

 surface is rarely, if ever, seen, only an approximate idea 

 can be formed. On Sowera it is, by aneroid measure- 

 ment, about 1,000 feet, or perhaps rather more, as the 

 observation was not taken on the highest peak. About 

 Guna Guna it does not much exceed half that thickness. 

 At Adigrat it appears to be intermediate in amount. 



No fossils were met with in this group, although 

 portions of" it, the shales especially, were much searched 

 for organic remains. This is unfortunate, for its position 

 in the geological series can only be approximately deter- 

 mined. By Messrs. Ferret and Galinier it was classed, 

 with doubt, as tertiary. There can be but little doubt 

 that it is miich older than this, from its relations to the 

 Antalo limestone ; but its true age is still uncertain. 



As above remarked, it invariably rests upon the meta- 

 morphics ; no, other rocks have been observed to inter- 

 vene. In the neighbourhood of Senafd and Adigrat, the 

 only rocks seen resting upon it are traps, which are 

 apparently conformable at the latter place, but quite 

 unconformable at the former. Their relations to the 

 sandstone will be described further on. 



About twenty-five miles south of Adigrat, at Mai 

 Dongolo or Wugula,^ sandstones are seen to dip below 



1 Not Agula, the name given to another camp, which is ten miles further 

 south. 



