468 



Sketches of the Meteorology, $c. 



[Oct. 



I have never seen the amygdaloid in situ ; and it does not appear to 

 be common in the Darwar district. Specimens of it have been brought 

 to me from the neighbourhood ofBeejapore. They contain zeolites, 

 green earth, and calcarious spar ; and resemble the same rock in 

 Britain. 



Ferruginous Claystone.— This is the laterite of Buchanan. It 

 covers very large tracts, both in India and the neighbouring countries. 

 It extends all along the western coast, from Fort Victoria to the south- 

 ern extremity of the peninsula.* It occurs in great abundance in the 

 Deccan, in Mysore, in the district of Cuddapah, and in Orissa.f It is 

 met with also in Ceylon ; and is almost the only rock which occurs in 

 Malacca^. 



This rock may be described, generally, as consisting of claystone, 

 more or less impregnated with iron, and having a massive, perforated, 

 or cellular structure. It frequently contains, imbedded in it, small 

 masses of clay, quartz, or ironstone. In its native beds, a short way 

 under the surface, it is so soft that it can be easily cut with a hatchet 

 or spade ; and, when sufficiently compact, and not containing imbedded 

 portions of quartz, &C it is cut into square masses like bricks, and is 

 used as a building stone. Hence Buchanan gave it the name of late- 

 rite ; and its names, in the native languages, are derived from the 

 same circumstance. When these square masses are exposed to 

 the air for some time, they become very hard ; and, when not 

 exposed to constant moisture, they answer admirably as building 

 stones. Most of the handsome Roman Catholic churches at Goa are 

 built of this claystone or laterite. In the principal fronts of these 

 churches it is covered with plaster ; but, in other parts, it is left bare, 

 and completely retains its hardness when exposed to the atmosphere. 



The ferruginous claystone occurs in different parts of the Darwar 

 district; but principally in the western parts, and on the summits of 

 the ghauts. Scarcely any other rock is seen in the Goa territory, and 

 it extends almost uninterruptedly from Goa to Honoor. It is found 

 resting in different situations, on granite, transition rocks, trap, and 

 sandstone. It is a very curious and interesting circumstance in regard 

 to the geognostical situation of this rock, that it is found resting upon 

 granite and transition rocks along the coast, and is again found resting 

 upon the same rocks at the summits of the ghauts, at an elevation of 

 several thousand feet. It forms, along the coast, a succession of 

 rounded hills ; and, towards the sea, it generally presents mural preci- 

 pices. I have never seen beds of any other rock alternating with it ; 



* Vide Mr. Calder's paper in the Asiatic Journal for October, 1828. 



t Vide Asiatic Researches, vol. xv. p. 177. 



t Vide Finlayson's Mission to Siam and Hue, p. 37. 



