by pentagon, hexagon, or multangular stones, placed 

 one upon another, are commonly supposed to be formed 

 by a deposition of stony matter from an aqueous fluid. 

 On the contrary, it is evident from various considerati- 

 ons, respecting their structure and phenomena, that thev 

 are concretions of a peculiar kind, generated by an ig- 

 neous fluid. They are peculiar to volcanic countries, 

 and differ in every respect from the crystals produced 

 by the slow and successive precipitation of the stony par* 

 tides contained in water. Their formation is owing to 

 an intrinsic principle of organization, operating on an ig- 

 nified fluid : on the concretion of which that principle 

 may be supposed to have operated simultaneously in a 

 large mass, and to have produced these bodies in the 

 same manner, as a linget of metal concretes at once in 

 the mould. 



In Persia there is a subterraneous fire of a very harm- 

 less nature. It rises out of the ground about twenty 

 miles from Baku, and three from the Caspian sea. 

 The ground is rocky, but has a shallow covering of 

 earth. If this be any where scraped off, and fire ap- 

 plied to the place, it catches fire immediately, and burns 

 without diminution, nor ever goes out, unless you throw 

 cold earth over it, by which it is easily extinguished. A 

 piece of ground, about two English miles in extent, has 

 this wonderful property. In many parts of it there is a 

 continual flame : the chief is in a hole, about four feet 

 deep and fourteen in diameter. This is said to have 

 burned many thousand years. They burn stones into 

 lime, by filling a hole in the ground with them, and then, 

 putting a lighted candle into the hole. The fire imme- 

 diately kindles, and in about three days burns the stones 

 sufficiently. 



It is remarkable, that this flame, how great soever it 

 be, gives neither smoke nor smell. There is much 

 naptha all about the place, though not just were the 

 fire is. 



Doubtless an inflammable vapour issues in abundance 

 out of the ground in this place. Something of the same 



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