MEMOIRS 



OF 



THE GEOLOGICAL SURVEY OF INDIA. 



Geology of the neighbourhood of Salem, Madras 

 Presidency, with special reference to Leschenault de 

 la Tour's observations. By Thomas H. Holland, 

 A.R.C.S., F.G.S., Officiating Superintendent, Geological 

 Survey of India. 



I.-INTRODUCTION. 



The town of Salem and the Shevaroy bills are included in the 

 north-west quarter of sheet 79 of the Indian atlas. This section of 

 the sheet has been geologically mapped by Messrs. W. King and R. 

 Bruce Foote, and described in their memoir " On the Geological 

 structure of parts of the districts of Salem, Trichinopoly, Tanjore 

 and South Arcot in the Madras Presidency. 1 " The few scattered 

 geological observations which had been made previous to the system- 

 atic survey carried out by Messrs. King and Foote are summarised 

 in their memoir, since the publication of which very little has been 

 added to our geological knowledge of the area. 



In 1889, however, Prof. A. Lacroix published a detailed 

 petrographical description of a very interesting series of specimens, 

 stated to be "from the neighbourhood of Salem, " and collected by 

 Leschenault de la Tour in the beginning of the century. It was with 

 a view to obtaining information concerning the geological relations 

 and precise localities of these rocks that I spent a short time in the 

 year 1897 examining the immediate neighbourhood of Salem. 



1 Mem., Ceol. Surv., Ind, t Vol. IV (1864), pp. 223—386. 



( 1 ) 



