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Memoir on ike Geology of the 



[Oct. 



forming a tube, with the hand or a roll of paper, to look through. 

 Nature has done at this Gap, precisely what the painter has found 

 advantageous to simplify the perspective, divesting it of all other lights 

 and objects, which would distract the attention of the beholder from 

 the principal object. The Gap itself forms a paltry view, being too 

 near; but it serves to heighten the beauty of other landscapes and 

 objects, and thus becomes essential to the picture. But, at this spot, 

 there are many points of view, seen through the chasm, that are most 

 wonderfully striking. 



From the outside of the pillars forming the Gap we see, jutting down 

 towards the Malabar, two sharp ridges, like balustrades to huge stairs 

 leading to this gigantic doorway, and which, gradually decreasing in 

 height, sink at last in the plains of Malabar. 



These plains form one view in the picture, intersected in all possible 

 directions by numerous water-courses, lakes and tanks, which irrigate 

 these extensive tracts, the sight of which relieves the eye from the 

 fatiguing sensation produced by the wild mountain-scenery above. 



Another, and perhaps the most picturesque, view, is that of the hills 

 of Malliallum, which intersect a portion of the plain, in humble but 

 pleasing undulations of a bluish colour; the red clouds hovering above, 

 and the blue firmament surrounding them, form a scene of grandeur 

 worthy of the pencil of Claude de Lorraine*. 



The geological features of the hills forming the Gap have already 

 been mentioned. That to the left from the base of the Gap to the sum- 

 mit (which may be between five and six hundred feet in both hills), is 

 basaltic overlaying pegmatite. The hill to the right is granite, having 

 numerous dykes and loose boulders of basalt, on its declivities and at 

 the summit. 



A question naturally arises at the sight of this vertical chasm, with 

 perfectly parallel sides. Has this Gap been produced by the corrosion 

 of the waters of rivers, charged with detritus, pebbles, blocks and sand ? 

 The present conformation of the Koondahs does not warrant such a 

 supposition ; the Gap being at a higher level than all the valleys in 

 the group. Even supposing that this spot had been thousands of feet 

 lower than the present level, it is exceedingly improbable that the 

 chasm could have been cut by the erosion of water ; because, the 

 edges of the two vertical rocks forming it are sharp and quite parallel, 

 without having the slightest appearance of that smoothness which 

 rocks that have been eroded invariably offer. 



The hills east of Sispara are granite (No. 151) ; notwithstanding 



* The annexed is from an etching by Captain Barron taken from a painting he has exe- 

 cuted in oils, which exhibits an exact representation of the splendid scene I have attempt- 

 ed to describe. 



