ALUM MINES OF AXJBIX. 357 



inclining 35* or 40«' W. S. W. It was got out bymeans of 

 Jevels, and with so ranch the more ease as the mountaio ^ 

 slopes to the north. Each seam having been worked in sc. 

 Teral places, and to some distance, as 80 or 100 met., the 

 £re has made more ravage, than at either of the other 

 three places. Notwithstanding the length of time, the acti. 

 ▼ity of the fire has not abated, at least in the higher parts. In 

 fact we see there the sunken surface of the earth iatersected 

 by long and deep fissures, the sides of which are in the highest 

 state of incandescence, and from which flames, accompa* 

 nied with suffocating vapours, are continually escapuig. In 

 a word, the solfaterra of Fontaines presents the most cu- 

 rious combination imaginable of all the phenomena above 

 described*. 



The vitrified, scorified, and decomposed matters, that fill 

 the sp^ce occupied or traversed by the fire, are very rich ia 

 aluminous salts. „ 



The alum mine of Buegne is at the top and on the back Mine of 

 of the hill of Buegne to the east. It is about 2 kilom. [1 1 ^"^i*"** 

 mile] west of Aubin. It is the result of the spontaneous 

 combustion of a single scam of coal, which commenced 

 twenty years ago, and has lost nothing of its activity. This 

 seam is several yards thick, and runs east and west, as the 

 ridge of the hill does. Its dip is about 45** south, and 

 consequently opposite to the slope of the hill. It is 

 easy to distinguish the outcrops of this scam on the parts 



• The aspect of the alum mine of Fontaines, the desolation Difference be- 

 and broken state of tlie ground, at first view suggest the idea of tween these 

 volcanic phenomena. But on a more attentive examination wcg canic 

 perceive, that the earth has been deranged only by s-rnking in ; 

 that there is no fissure which has any resemblance to the mouth of 

 a crater ; that the scorification and vitrification have been effected 

 on the spot; that the products of these two operations do not re- 

 semble lavas; that the vapours always very evidently contain 

 Jjitumen, and never muriate of ammonia; that the sal^ formed, 

 are sulphates ; that besides no detonation is ever heard, and the 

 groUiUd experiences no commotion that can be compared to an 

 earthquake: in short, if we set aside the heat and light produced 

 by the combustion of the coal, and the aqueous and acndosulphu- 

 rous vapours emitted, nothing similar to volcanic phenomena ever 

 takes place. 



of 



