298 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



odour. Some patches of compact, white limestone repose upon the 

 slope of the cone. No igneous rocks occur in the immediate vicinity, 

 but the great range is composed of granite. 



The eastern boundary of the Mergaver Plain is a moderately ele- 

 vated range, which is, I believe, composed of altered limestone. 



A low and broad elevated tract alone separates the plain of Mergaver 

 from that of Desht. In a ravine in the Frontier Range, at the 

 junction of these plains, is a bed of iron-ore, which is disseminated in 

 large irregular masses of clay- iron-stone, imbedded in a micaceous rock, 

 coloured with the oxide, but not sufficiently rich to be worked. 



All along this portion of the Frontier there are indications of the 

 presence of ores, especially copper and iron ; but the jealousy of 

 the natives is such as to render it extremely difficult for a passing 

 traveller to obtain any accurate information. I am quite convinced 

 that a careful investigation of this region would bring to light great 

 mineral riches. It is well known that valuable mines are worked in 

 the districts to the west ; for instance, at Jiilamerk, where the mines 

 of sulphate of arsenic are among the most important belonging to 

 the Turkish Government. These, if properly conducted, would 

 prove to be a source of large revenue. But generally, however rich 

 a mine may be, the great want of fuel and water throughout this 

 region would be a bar to its being worked with advantage. To this 

 difficulty must be added the inclemency of a long winter-season, and 

 the utter ignorance of the natives in the art of practical mining. 



Section between V'rumia and Gdwdr. Fig. 15. 



The alluvial plain of U'rumia is bounded on the west by a con- 

 siderable range of sandstone, which separates it from the plain of 

 Desht. 



This range rises at Seyr Dagh to the height of 7260 feet above 

 the sea (according to barometric measurement made by the members 

 of the American Mission), and has a constant dip of 5° or thereabouts 

 to the N.E. 



Following up the course of the Shaher stream through the range, 

 the geologist recognizes in the beds composing it characters which at 

 once class them with the Gypsum-series described in Part I. of this 

 paper (p. 254), as occurring along the western skirts of the Zagros, 

 between Behbehan and Mosul. 



These characters are not to be mistaken. The sandstones of the 

 Seyr Dagh belong to the uppermost part of the gypsum-series, — in 

 the lower beds alternating with marls and impure limestones, and 

 in the upper with conglomerate-gravels. The colour of the sand- 

 stones is yellow or brownish ; in this respect differing from the same 

 rocks in the west, which are generally reddish. 



The upper beds are in places covered unconformably by a mass 

 of loose gravel, or gravel- conglomerate with calcareous paste. 



It is remarkable that the gravels associated with the sandstones 

 are composed of pebbles of blue and white altered limestone, quartz, 

 micaceous sandstone, and quartzose sandstone, without any inter- 

 mixture of igneous rocks ; on the other hand, the superficial gravel 



