558 APPENDAGE TO THE VOLCANIC. 



was new to me, and excited my curiosity on all 

 points. It may well be supposed, that I did not 

 confine myself to this idle inspection; in travers- 

 ing with an uncertain step this smoking and 

 burning surface, which often obliged me to turn 

 from one part to another; in walking on this 

 demolition of substances, to admire, as near as 

 possible, the different apertures of fire, which I 

 was accustomed to distinguish ; I fully perceived 

 that those confused remains, deserved a separate 

 and detailed examination : their different tints of 

 white, yellow, yellowish, violet, greenish, or 

 other colours that they have acquired according 

 to their nature, according to the duration or de- 

 gree of the fire, made them already remarkable. 

 " They are all either calcareous, or verifiable: 

 the greater part resemble baked bricks, some are 

 whitened, calcined, reduced to lime, and are 

 changed into a kind of red pumice, or bear other 

 marks of scorification in different degrees, some- 

 times with mixtures of stones more or less altered, 

 as veined tufos, formed of ashes, and lajrillo 

 agglutinated together. Several of these stones, 

 and in great numbers, are visibly and abundantly, 

 either impregnated, or incrusted with salts and 

 sulphurs. Here stones of different sizes, cover 

 thick beds of ashes, reduced by the strength and 

 duration of the fire, to an impalpable powder, 



