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JOURNAL, R.A.S. (CEYLON). [VOL. II., PART II. 



NOTES ON THE GEOLOGY OF CEYLON. 

 LATE RITE FORMATION. — FLUVIATILE DEPOSIT 

 OF NUWARA ELIYA. 



By E. F. Kelaart, m.d., f.l.s., f.g.s. 



Assistant Surgeon to the Forces. 



si Even those who run may read in the Book of Nature, and if they read 

 there is no reason why they should not note for the benefit of those who have 

 not the opportunity of studying from the same pages." — Newbold. 



Though the geological formations of Ceylon are of a simple 

 nature, and described as such by writers, that attention has 

 not been paid to the laterite formation of the Island which 

 it deserves : some have called it decayed clay ironstone ; 

 others have described it to be granitic rocks weathered in situ. 

 It has not, however, been so slightly regarded by Indian 

 geologists. Their more recent researches have discovered 

 new features in this peculiar formatiou, which have thrown 

 great doubts as to its being the mere result of disintegrated 

 or decomposed hypogene or trapean rocks in situ. Captain 

 Newbold of the Madras Engineers has even gone so far as 

 to suspect it to be of tertiary origin. It is with a view of 

 drawing the attention of observers in this Island, for a more 

 complete elucidation of this subject, that this communication 

 is submitted to the Ceylon Asiatic Society. 



The term laterite (derived from later, a brick) is applied 

 to those masses of reddish clay, more or less indurated, and 

 containing pebbles or crystals of quartz. It is called by the 

 Sinhalese cabook, and is used extensively for building pur- 

 poses. There are several varieties of laterite, and which 

 admit of classification : — (1) Laterite, properly so called, of a 

 hard compact, almost jaspedeous rock, formed of indurated 



