the HIGHLANDS of SCOTLAND. 9 



bouring hills is there, fo far as I could obferve, the fmalleft ap- 

 pearance of that kind. 



The vitrified matter on the fummit of this rock is> therefore, 

 the only circumflance which pofitively vindicates the effect of 

 fire ; and this I mail now proceed to examine. 



The Society have already had before them fpecimens of this 

 burnt or vitrified matter. I fhall, therefore, fuppofe, that they' 

 are fufficiently acquainted with its appearance. It will be re- 

 collected, that in none of the fpecimens which were produced, 

 was there any thing like a total fufion of the materials. Some 

 parts of the mafs feemed to be portions of argillaceous and un- 

 vitriable ftone ; others of ftones of which a part had been in 

 fufion, while the reft remained in its natural flate. Thefe cir- 

 cumftances, of themfelves, are fufficient to diflinguifh this fub- 

 flance from volcanic lava, which is an uniform homogeneous 

 mafs, of which every part has been in a flate of fufion. Nei- 

 ther has this vitrified fubflance the appearance of thofe fcorice 

 thrown up from volcanos, which are probably the fcum of the 

 lava, or fuch parts of the materials as either never were fufible, 

 or have loft their fufibility and principle of inflammability : 

 For the burnt fubflance on the top of Craig-Phadrick is rather 

 a mixture of fufible with unfufible fubftances ; many parts ap- 

 pearing to have been in the mofl perfect; fufion, while others 

 have remained in their natural ftate. 



But the circumtlance which, in my apprehenfion, evinces, 

 in the moft fatisfaclory manner, that thofe appearances of the 

 effect of fire on the fummit of this hill, are not the operation of 

 nature, but of art, is the regular order and difpofition of thofe 

 materials, the form of the ground, and the various traces of 

 fkill and contrivance which are yet plainly difcemible, though 

 confiderably defaced, either by external violence, or by the ob- 

 literating hand of time. To proceed regularly in examining 

 thofe appearances of artificial contrivance, I return to that 

 winding road I before mentioned, which is evidently cut 



Vol., II. B through 



