

584 Notes on Geology and Mineralogy of Afghanistan. 



these run in a direction from N. E. to S. W., and the dip of 

 the strata where apparent, is easterly with a little northing. 



On the west of the town, at about 2J miles distant, rises a 

 mass of greenstone, black and polished on the exterior sur- 

 face, and exhibiting the stair-like structure so common to 

 this class of rocks ; with this is associated beautiful veins, 

 and dykes of white clay-stone, and common serpentine of 

 several shades of green and red ; thin flinty slates and red 

 ferruginous clays much indurated, as well as red and green 

 jaspers, are also disposed conformably along the base of the 

 dark blue limestone,* which forms the dividing range be- 

 tween the Candahar valley and that of the river Argandab, 

 which latter, farther away to the westward, is bounded by 

 another parallel range of mountains of considerable height, 

 and termed Koh i-Shahmuksood. Both valleys are termi- 

 nated to the south by the desert tract of red sands, from 

 which they are divided by narrow rivers ; the Candahar 

 valley being crossed by the Doree, and the Argandab valley 

 by the westward turn of the river of that name. 



The soil of the cultivated lands around Candahar is rich 

 and productive, being composed of calcareous and arenace- 

 ous clays, and other matter derived from the decomposition 

 of trap rocks. The cultivation is entirely irrigated by 

 canals connected with the Argandab, whose waters are 

 brought through breaks in the limestone range. Without 

 this aid the city would be deprived both of cultivation and 

 water, and the whole valley would become an arid waste ; 

 even as it is, with an abundant supply from the canals, the 

 central line only is under cultivation, all beyond rising gra- 

 dually on either side towards the mountains, and presenting 

 a barren tract thickly strewed with rolled pebbles of various 

 kinds and sizes, and such indeed are the characteristic 

 features of every valley in this part of Afghanistan, those 



* Specimens of this rock lately shown to a practised Geologist, Mr. Reckendorf, 

 were pronounced by him to belong to the Muschelkalk of Germany. 







