1836.] 



Keelgherries and Koondahs, 



243 



of the rocks forming the Neelgherries. Although their contour is even, 

 smooth, rounded, and, as it were, undulating, the fundamental rocks of 

 which they are composed belong to the primitive class. 



Their outline resembles those hills and eminences we meet in 

 districts, resulting from tertiary or alluvial deposits. What the rock 

 is, which gives those hills the rounded form they exhibit, will be shewn 

 hereafter. 



With the exception of some vertical cliffs and mural precipices, seen 

 in the boundaries of this elevated plateau, and a few projecting masses 

 of the fundamental rocks on the summits and declivities of these hills', 

 the whole group is uniformly covered by a thick stratum of vegetable 

 earth (No. 1*), which overlaying a thicker stratum of red earth, (to be 

 described in the sequel), supports numerous plants, chiefly grasses, 

 which, growing most luxuriantly in thick contiguous tufts, give the sur- 

 face a smooth carpet-like appearance. This vegetable earth in general 

 is clayey, and of a grey colour, and very friable. On this soil we occa- 

 sionally see small rounded pieces of the decomposed subjacent rock, 

 bestrewed particularly on those spots where blocks of the decomposing 

 rock are seen jutting through the soil. 



This vegetable soil is replaced in the low valleys and flats at the foot 

 of the hills, by a black soil, such as we frequently see forming the peat- 

 bog in swampy grounds, in which a large quantity of vegetable matter 

 is decomposing (No. /J). 



This soil is of a black, or deep brown, colour j of tenacious consist- 

 ence, when moist; crumbling into powder, and off en splitting into 

 prismatic mnsses, when dry. At first sight, it resembles the black soil 

 of the plains of India. From this last, however, it seems to differ 

 greatly, in containing a large quantity of carbonaceous matter, and 

 much oxide of iron. 



To deprive this black so'l of the greater portion of its humidify, I 

 exposed it to a heat, sufficient to melt lead, and after having weighed 

 a certain quantity of it, subjected it to an intense heat for an hour » 

 after this, it had lost more than '^5 per cent, of the original weight, and 

 had changed into an ochrey red powder (No. 3), without undergoing any 

 vitrification, as is the case with the black soil of the Deccan, (Voysey). 

 It would therefore appear, that the loss is owing to the oxidification 

 and consequent volatilization of the carbonaceous matter. 



This soil, although more frequently found in low situations, is often 

 seen in a thick stratum on the declivities of the hills, such as on the 

 slope of one of the Doodabetta group, facing the cantonment ; on that 

 of the Elk Hills, (S.) above South Downs ; near the Kaitee Pass, and in 



* The figures refer to illustrative specimens presented for deposit in the Minernlogical 

 Cabinet of the Madras Literary Society.— Editor, 



