1 6 St J ago. 



PAET I. 



calcareous powder. This structure immediately re- 

 minded me of the appearance in badly kneaded dough, 

 of balls and drawn-out streaks of flour, which have re- 

 mained unmixed with the paste ; and I cannot doubt 

 that small masses of the lime, in the same manner re- 

 maining unmixed with the fluid lava, have been drawn 

 out when the whole was in motion. I carefully ex- 

 amined, by trituration and solution in acids, pieces of 

 the scoriae, taken from within half-an-inch of those cells 

 which were filled with the calcareous powder, and they 

 did not contain an atom of free lime. It is obvious 

 that the lava and lime have on a large scale been very 

 imperfectly mingled ; and where small portions of the 

 lime have been entangled within a piece of the viscid 

 lava, the cause of their now occupying, in the form of 

 a powder or of a fibrous reticulation, the vesicular 

 cavities, is, I think, evidently due to the confined gases 

 having most readily expanded at the points where the 

 incoherent lime rendered the lava less adhesive. 



A mile eastward of the town of Praya, there is 

 a steep-sided gorge, about 150 yards in width, cutting 

 through the basaltic plain and underlying beds, but 

 since filled up by a stream of more modern lava. This 

 lava is dark gray, and in most parts compact and rudely 

 columnar; but at a little distance from the coast, it 

 includes in an irregular manner a brecciated mass of 

 red scoriae mingled with a considerable quantity of 

 white, friable, and in some parts, nearly pure earthy 

 lime, like that on the summit of Red Hill. This lava, 

 with its entangled lime, has certainly flowed in the 

 form of a regular stream ; and, judging from the shape 

 of the gorge, towards which the drainage of the country 

 (feeble though it now be) still is directed, and from the 

 appearance of the bed of loose water-worn blocks with 

 their interstices unfilled, like those in the bed of a 



