1 72 GEOLOGY. 



the Antalo limestone. The Adigrat sandstone is traced, 

 almost without a break, from the neighbourhood of 

 Halai, Takonda, and Senaf^, to within about six miles 

 east of Dongolo ; but then there is a break, and meta- 

 morphics intervene, so that the beds at Dongolo are not 

 connected with the mass of the formation. They differ 

 also in colour, being red ; and instead of being horizontal, 

 as at Adigrat and generally throughout Northern Tigrd, 

 they dip at a considerable angle to the southward. 



These differences do not appear to be of much im- 

 portance. The colour of the sandstone is occasionally 

 red everywhere, and is very liable to vary ; and although 

 the greater portion of the formation is perfectly hori- 

 zontal, it does dip in places. Besides, the Antalo lime- 

 stones are also horizontal in general, although they too 

 are considerably inclined near Dongolo. Moreover, the 

 sandstone, a little farther west than Dongolo, forms 

 massive craggy hills, standing out above the plain of 

 the metamorphics, which is higher than the valley in 

 which Dongolo lies ; and these crags, although formed 

 of inclined beds, resemble closely those of the Adigrat 

 sandstone further to the eastward and northward ; in- 

 deed, they have all the appearance of being outliers 



c 2, 



Sketch section of relations tetween trap, limestone, sandstone, and metamorphics 

 near Dongolo : a, trap ; h, limestone ; c, sandstone ; d, metamorphics. 



from the Adigrat hills. The accompanying sketch sec- 

 tion will give some idea of the apparent relations of the 



