oO Dr Kelaart's Notes on the Geology of Ceylon. 



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 for- 

 mation 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 disinte- 

 gration, some of the original stratification (often seen running 

 almost vertically) of the gneiss being preserved. 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 con- 

 tinuity in the hills of the harder variety of laterite. Here, 

 certainly, the appearances are favourable to the opinion that 

 laterite is a distinct formation 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 Mutwall, and in the Fort 

 of Colombo. Laterite may also be seen, says Captain New- 

 bold, capping hypogene or trap-rocks of great elevations, 

 while the adjacent hills, composed 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 be 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, fifteen miles south of Quilon, a layer of lignite 

 in the laterite, imbedded in a stratum of dark shale and clays. 

 Lignite has also been seen in the laterite of Travancore ; 

 and graphite has also been observed there. These are the 

 observations which have made Newbold and others view the 

 laterite of Southern India as a distinct formation, more recent 

 than any of the rocks. Till similar features are observed in 

 some of the laterites of Ceylon, we are obliged to regard them 

 to be the weathering of rocks in situ. 



To comprehend, how a hard compact rock like granite or 



