44-2 Capt. Cullen on the Geology of the Carnatic. 



the Kistnah to the Pennar, is composed of that rock. Some 

 of the limestones, or marbles, may prove to possess that pecu- 

 liar combination of clay, silica, and carbonate of lime, which 

 is found to afford those valuable cements having the property 

 of setting under water. Major De Haviland, of the Engi- 

 neers, had, I believe, already directed his attention to the dis- 

 covery of such varieties. 



From my imperfect acquaintance with the subject, I am 

 aware, that in the above summary of the situations of the rocks 

 over so great a space, I must necessarily have omitted noticing 

 many circumstances which it would have been of consequence 

 to record ; but daily marches of from fifteen to twenty miles 

 in the hottest season of the year, may of themselves be deemed 

 an apology for those, as well as other inaccuracies that may, 

 perhaps, hereafter be discovered. I have, however, endea- 

 voured to be faithful in my narrative of facts ; and as such, in 

 the present limited state of published information on these 

 subjects in this country, they will, I trust, be received with in- 

 dulgence. W. Cullen, 

 Bellary, May 1823. . Captain of Artillery. 



The altitudes, in the section which accompanies this paper, 

 are deduced from barometrical observations, regularly made 

 throughout the march. Observations of the maximum and 

 minimum heights of the column of mercury were taken daily 

 at each stage, and the mean of these was generally used in 

 the calculations. Corresponding observations were obligingly 

 furnished to me by Mr. Goldingham from the observatory ; 

 from a comparison with which, and with another series of ob- 

 servations made by Major Beckett at Bellary, the altitudes of 

 the several stations have been determined. 



In former instances, most of the approximate altitudes which 

 I have had opportunities of ascertaining in different parts of 

 the peninsula, have been deduced solely from my own obser- 

 vations, a mode originating in some degree in necessity, and 

 subsequently adhered to, partly from the same cause, but partly 

 also from cnoice, from a desire to ascertain how far such ap- 

 proximations might be depended upon. 



Few or no barometrical observations were at that period 

 regularly made at any of the inland stations under this Presi- 

 dency ; and the stations where such records were kept were so 

 remote from each other, as well as from my routes, as to oc- 

 casion frequently very great differences in the altitudes derived 

 from them. 



I proposed accompanying this paper with a copy of my own 

 barometrical observations, as well as of the corresponding 



ones 



