1849.J Siatistics of the Vircar of Dowlutahad, 48S 



6. Amygdaloid Trap. The basis of this rock is wacke various- 

 ly coloured from grey to buff having shades of light green and pink 

 with every gradation of hardness : it is seen interposed between 

 darker basaltic strata the association with which gives the streaked 

 appearance to the bared sides of the mountains. Numerous silicious 

 minerals are scattered throughout the rock of all forms and sizes ; 

 oftentimes irregular cavities of large dimensions are seen, whose 

 sides are lined with calcareous spar, rose and rock crystals, and ca- 

 chalong. 



7. Red Amygdaloid Clay Stone. This rock is very frequent 

 along the lower basis of the hills, its color varying from a pinkish 

 hue to a bright brickdust red, and chocolate, it contains cavities oc- 

 cupied with shining zeolitic spar, or tabular and flattened chalcedo- 

 nic minerals, coated with chlorite earth. It is not unusual to find 

 the cavities empty and their sides covered with earth of a deep yel° 

 low or light green color. 



8. Red Clay Stone Porphyry. A rock with sharp fracture and in- 

 clined to a fissile character. Its imbedded minerals are zeolite and 

 eilicious crystals generally in small rounded forms : sometimes the 

 contained minerals blend into the general mass, as specks or splashes, 

 or by their infrequent occurrence confers the condition approaching 

 to a simple rock. It is susceptible of a high polish and is admira- 

 bly adapted for ornamental architectural purposes. 



9. Ferruginous Clay Stone. This is the Ferruginous clay stone 

 of Dr. MacuUoch, and to be distinguished from the rock so termed 

 by Dr. Buchanan, which is laterite. It is generally of a purplish 

 grey color within, coated without with a brickdust or livid red ; usu- 

 ally seen under semi-columnar basalt, and reposing on globular trap 

 rocks, varying in breadth from six or eight inches in two or three 

 feet. Its structure is best observed in the beds of nuUas, or passes 

 in the hills where it may be seen taking a waving line as if adapting 

 itself io the inequalities of the rock it reposes on ; where its surface 

 is exposed (which is reddened) there are seen what at first sight has 

 much the appearance of ripple marks being slight ridges or eleva^ 

 tions arranged in semi-circular sweeps in an uniform manner, which 

 project at their centre, as if produced by the force of some impul- 

 sive power, and terminate in a thin rounded margin, a series of cir- 

 cular elevations are sometimes seen as though a viscid masSj in fio'i^'- 

 TOi), XT, NO, %x%yi. 0 1 



