150 THE GEOLOGIST. 



not forget a singular circumstance, namely, that the town of Mont- 

 pellier is built upon a mine of pure mercury ^ He had found this 

 precious metal in many of the streets, in the rue Carbonerie, the rue 

 de riJniversite, the Grande rue, the Halle aux Poissons (fish-market), 

 &c. In 1837, M. Marcel de Serres and Leymerie described the 

 ground in which the metal lay, and moreover made known the existence 

 of the latter in the soil of a field which had always been remarkable 

 for its sterility. A few days ago, K. de Rouville and M. Marcel de 

 Serres have again written upon the same subject. 



The reason why so many observers should have called attention to 

 i;his fact is doubtless to be found in the curiosity of such a discovery. 

 In fact, pure quicksilver has, up to the present time, not only been 

 considered a rare mineral, but has almost always been found near the 

 middle strata of the earth's crust, and in those strata which repose upon 

 crystalline rocks. It has, indeed, been mentioned by Mr. Daniel Sharpe 

 as having been met with in the Tertiary sand on which the capital of 

 Portugal is built; and in 1847, some workmen who were laying down 

 gas-pipes at Lyons were surprised at seeing a remarkable quantity of 

 quicksilver filtering, as it were, through the soil in the very centre of 

 the town. The metallic mine indicated by Mr. Sharpe was actually 

 worked for some time j but the presence of mercury at Lyons was 

 attributed to the ficility with which this slippery metal, much employed 

 in the manufactories, escapes from the hands of the workmen. 



At all events, M. de Rouville has recently discovered, at Montpellier, 

 a new deposit of metallic mercury, which, until now, had never been 

 remarked. In building the foundation of a new fish-market, near the 

 place where the old one stands, a quantity of earth was removed, and 

 a species of pudding-stone, containing the precious metal, laid bare. 

 M. de Pouville describes this pudding-stone as formed of large frag- 

 ments of limestone strongly cemented together, containing a little 

 silica. It is of a reddish colour, and reposes on grey fresh-water marl, 

 in which M. Paul Gervais formerly discovered the teeth of a new 

 species of monkey. According to M. Marcel de Serres, the following 

 is the description of the soil in which the mercury is found : — 



''Uppermost, a bed of reddish mud, then a thin layer of grey marl 

 mixed with gravel and calcareous pebbles about as large as the hand. 

 Next comes a layer of whitish marl, and under this a very greyish 

 calcareous sandstone, containing calcareous pudding-stone and pebbles 



