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



difference of opinion rests upon the question whether the 

 disintegration or decomposition took place in situ, or 

 whether the disintegrated masses were deposited or brought 

 from a distance and' laid over the rocks on which laterite 

 now lies ; or, in other words, is it a formation in itself 

 derived from rocks which formerly existed ? 



To the former view (weathering in situ) there are many 

 more supporters than to the latter ; and among them our late 

 much lamented Dr. Gardner, who from observations both in 

 this Island and on the Continent of India, attributed the 

 formation of laterite to the simple decay of gneiss or 

 granitic rocks. I cannot but agree with him that in many 

 cuts or sections of the rock nature is detected in the act of 

 disintegration, some of the original stratification (often 

 seen running almost vertically) of the gneiss being pre- 

 served ; in other places it is difficult to trace where the 

 gneiss terminates and the laterite commences, one as it 

 were running into the other. But I must observe that 

 I could never trace this continuity in the hills of the harder 

 variety of laterite. Here, certainly, the appearances are 

 favourable to the opinion that laterite is a distinct forma- 

 tion of itself. And yet this hard laterite rests on gneissic 

 rocks, as is seen at the bottom of wells sunk in the lateritic 

 hills at Mutwal and in the Fort of Colombo. Laterite may 

 also be seen, says Captain Newbold, capping hypogene or 

 trap rocks of great elevations, while the adjacent hills, com- 

 posed of an exactly similar rock and forming a continuation 

 of the same bed equally exposed to the action of the weather, 

 are quite bare of the laterite. He also observed laterite 

 resting on limestone without a trace of lime in the 

 laterite. If my information is correct, laterite is also seen 

 over some of the limestones of Jaffna in the north of the 

 Island. General Cullen found on the western coast of 

 India, 15 miles south of Quilon, a layer of lignite in the 



