178 PHILOSOPHICAL TRANSACTIONS. [aNNO 171 5. 



pine-trees that grow on both sides the road for a great way. Among these 

 trees, not a great height in the air, we saw the sulphur discharge itself like a 

 squib or serpent made of gunpowder, the fire running downwards in a stream, 

 and the smoke ascending upwards from the place where it first took fire ; and 

 like this we saw another, while we lay under the rocks the next night at la Stancha, 

 part of the way up the peak ; but I could not observe whether either of them 

 gave any report as they discharged. 



At three quarters after 4 we came to the top of this high rough and steep 

 mountain, where grows a tree which the Spaniards call el Pino de la Merenda. 

 The pine tree of the afternoon's meal. This is a large tree, and is burnt at 

 the bottom, by having had fires made against it; and in the burnt place there 

 issues out turpentine. At a few yards distance from this tree we had a fire 

 made, where we staid and baited our horses, and breakfasted ourselves. These 

 hills are very sandy, and a great many rabbits breed there; there is also much 

 sand found a great way up the peak itself, and not a great way below the foot 

 of the sugar-loaf. At three quarters after 5 we set forwards again, and at half 

 an hour past 6 came to the Portillo, which in Spanish signifies a breach or 

 gap. We saw the peak about 2 leagues and a half before us, covered still with 

 a cloud at top ; and the Spaniards told us we were come about 2 leagues and a 

 half from the port. 



At half past 7 we came to lus Faldas, tha:t is the skirts of the peak ; from 

 whence all the way to la Stancha, which is about a quarter of a mile up from 

 the foot of the peak, we rode over small light stones, about the size of one's 

 fist ; and a great many not much broader than a shilling : here if we kept the 

 beaten track, it was not deep ; but if we turned out of it, the horses went 

 almost over their feet. I alighted and made a hole there, thinking to find how 

 deep these little stones lie, but could not find the bottom ; which makes me 

 conclude they may cover the ground for a great thickness. 



There are a great many vast rocks, some of them about 2 miles from the 



foot of the peak, which the peakman told us was cast out from the top of the 



peak at the time it was a volcano ; many of them lie in heaps of above 6o yards 



long, and I observed that the farther these rocks lie from the foot of the peak, 



the more like they are to the stone of other common rocks: but the nearer we 



went to the peak, we found them more black and solid ; and some of them, 



though not many, were glossy like flint, and all extremely heavy. Those that 



shone so, I suppose retained their natural colour, but there are some that look 



like dross that comes out of a smith's forge, which was doubtless occasioned by 



the extreme, heat of the place they came from. Some of these large rocks 



were thrown out of the caldera or kettle in the top of the peak ; and others 



