546 J. G. MalcolmsoNj Esq.^ on the Fossils of 



have led to an extensive deposit of calc-tufF(Kunkur), at present forming along its base, and pro- 

 jecting sometimes half a foot from between the partings of the basaltic tables. — " The presence of 

 olivine, the soft wacke in which the globular basalt is imbedded, the less crystalline structure, 

 the passage into a porous amygdaloid, containing calcedonies, zeolites, &c., and the granite in 

 the neighbourhood of all the smaller masses differing little from that at a distance," may perhaps 

 be sufficient to distinguish these insulated basaltic hills from the greenstone*. 



On approaching- the Godavery, the granite in some degree changes its ap- 

 pearance, containing large and beautiful crystals of red felspar, occasionally 

 imbedded in veins of transparent quartz, clouded with spots and wavy lines of 

 a turbid milky colour. Greenstone dikes are there more common. The river 

 flows over granite, which is intersected by several dikes of greenstone, run- 

 ning more in a north and south direction than those above referred to, and ha- 

 ving many minute white crystals diffused through their substance. The dikes 

 project from 8 to 10 feet above the granite, and are divided into rhomboidal 

 masses by fissures, in which lime is deposited. The bed of the river is co- 

 vered by numerous fragments of calcedonies, zeolites, and other minerals found 

 in volcanic rocks ; and they have been cemented into a more or less solid calca- 

 reous conglomerate. The banks are composed of a black basaltic soil, from 

 the lower part of which, where it rests on the granite, as well as from the divi- 

 sions between the several layers of alluvium, thin slabs of a clayey calc-tuff 

 (Kunkur) project, and are connected above with portions formed round the 

 roots of plants, and below with other layers spread out between the different 

 strata of alluvial earth f. These appearances sufliciently indicate the neigh- 

 bourhood of the basaltic range of mountains, distinguished in Arrowsmith's 

 large map as the Sichel or Shesha hills, but which are locally known by the 

 name of the Nirmul range, from the large town situated six miles from the 

 difficult pass leading up the steep escarpment presented by their southern face. 

 None of the stratified primary rocks are seen at the foot of these hills in the 

 line of the section ; but twenty miles to the east of Nirmul, and a few miles 

 south of the mountains, hornblende slate occurs, resting on granite and quartz 

 rock. 



Iron Ore, Mines, and Manufacture of the Steel. — The magnetic iron ore, employed for ages in 

 the manufacture of the Damask steel used by the Persians for sword-blades, is obtained from 

 this schist. The mines I examined, are those of Deemdoortee, but the ore is extensively dis- 

 tributed. The minute grains or scales of iron are diffused in a sandstone-looking gneiss or mica- 

 ceous schist, passing by insensible degrees into hornblende slate, and sometimes containing amor- 



* Journal of the Asiatic Society of Bengal, February 1836, p. 105. 



f Further details on this part of the route will be found in some notes explanatory of a collec- 

 tion of specimens presented to the Asiatic Society of Bengal, and published in the Journal of that 

 Institution for February, 1836. 



