THE 



CALCUTTA JOURNAL 



OF 



NATURAL HISTORY. 



On the Schistose formations of the Table Lands of South 

 India, with the characters of Hornblendic rocks. By 

 Captain J. Campbell, Assistant Surveyor General, Ma- 

 dras Establishment. 



The whole of the South India with which I am acquainted, 

 is characterized by flat plains of an apparently general un- 

 deviating level, sometimes extending for many miles without 

 an eminence of any kind, and presenting therefore the most 

 monotonous aspect which can be imagined. From these in 

 some parts rise abruptly conical hills and ridges of granite, 

 as mentioned in the descriptions of the granite of the Barra- 

 mahal. The plains of the Cranatic, of the northern Circars, 

 of Trichinopoly, and of Salem, and also the Barramahal, all 

 present precisely the same appearances, changed only in 

 some parts by the greater frequency, or more close approxi- 

 mation of the granite hills. 



It is the surface of these plains which affords the arable 

 soils, and even in the smallest arable tracts which are found in 

 confined valleys on the summits of many of the table lands of 

 Salem, of Kimedy, and of Goomsoor, the formation is precise- 

 ly the same. 



The apparently perfect level of the surfaces of these plains 



is a deception, as may be seen by examining the beds of the 



principal rivers, which have so great a declivity as to run 

 VOL. II. NO. VII. OCT. 1841. 2 Q 



