414 Geological Sketch of the Neilgherries. [Aug. 



Their being almost in the middle of a district, in which, one of the 

 most interesting rocks in the Indian formations (the laterite) is found 

 developed in all its characteristic features, adds not a little to their 

 importance in a geological point of view. On account of their superior 

 elevation, they ought to be carefully examined by the geologist, 

 before he extends his researches to the other parts of the chain, of 

 which they form the most elevated point. 



It was, undoubtedly, after consideration of this kind, that the late 

 Doctor Turnbull Christie, of the Madras Medical Establishment, 

 had begun his geological survey of the peninsula from the Neilgher- 

 ries, as from a point where the rocks, found at a lower level, are seen 

 in their original state, unmodified, and unaltered by formations and 

 deposits, which events and revolutions, subsequent to the elevation of 

 the whole chain of the western ghats, must have produced; and had 

 his life been spared, he would, undoubtedly, have given to the public 

 the most accurate and comprehensive account of the geological form- 

 ations of this interesting part of India, and would have settled many 

 doubtful points in Indian geology, which now keep many of the ablest 

 geologists in a state of uncertainty and suspense. 



The few memoirs he published regarding the geology, not only of 

 India, but of those places through which he journeyed, particularly 

 of Sicily, show what was to be expected from a man, who evinced so 

 much information and accuracy of observation on those subjects. 

 Unfortunately for Indian geology, he was cut off at the very beginning 

 of his labours on these very hills, which had in preference attracted 

 his attention and researches. 



We are told that the experienced eye of the geologist can easily 

 guess the nature of the rock composing a hill or a system of hills, by 

 the simple inspection of its outlines: thus, spiry peaks show the 

 formation to be primitive ; rounded smooth outlines are indicative of 

 calcareous mountains ; while the castellated ruin-like appearance of a 

 mountain, is proper to the sandstone formation. 



This criterion, however, would lead into error regarding the nature 

 of the rocks forming the Neilgherries. 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 



40 miles, and their extreme breadth 15 ; taking in account the great undulations 

 of the surface, and the breadth above stated being pretty constant throughout, 

 their superficial extent may be fairly estimated at from 6 to 700 square geogra- 

 phical miles. — Baikie's Observations on the Neilgherries. 



