156 Intelligence and Miscellaneous Articles. 



buret of iron. The oxalate of copper is a blue powder insoluble in 

 water, which heated to redness aftords metallic and protoxide of 

 copper. — Jour, de Pharm., April, 1836. 



LOCALITY OF NATIVE MERCURY. 



M. deBonnardhas communicated to the Philomathique Society 

 of Paris, a notice by M. Alluaud, sen. of Limoges, respecting the 

 mercury of Peyrat-le-Chateau, department de la Haute-Vienne. 



This metal is found in the native state in a disintegrated granite, 

 which forms the esplanade of the ancient castle of Peyrat, on the 

 side of the royal road from Figeac to Montargis. M. Alluaud 

 describes the nature of the soil of the country, which is entirely 

 formed of various kinds of granite passing into each other, as 

 kaolen and gneiss, &c. On the esplanade of the castle of Peyrat, 

 M. Ranque, in clearing the soil and digging the foundation of a 

 house, found twelve pounds of native mercury, and other persons 

 also found some. M. Alluaud having made several excavations and 

 also examined the places, found the mercury disseminated in a fine- 

 grained granite, which was very quartzose, and the felspar was de- 

 composed. The metal does not exist throughout the rock, but 

 only in parts of it; no bed, vein, or fissure can be perceived. The 

 metal has been found at several distinct places, far from each other 

 and without any communication ; this circumstance is unfavourable 

 to the idea of an accidental infiltration from above, for in this case 

 the metal would have occupied a circumscribed situation in some 

 fissure of the rock. 



Notwithstanding the singularity of this locality of native mer- 

 cury in a primary rock which contains no indications of cinnabar, 

 and difficult as it is to draw a conclusion from an isolated obser- 

 vation confined to the narrow space of a few feet, M. Alluaud does 

 not hesitate to pronounce either that the mercury is disseminated 

 in the rock in small masses, irregular both as to form and extent, 

 and in this case that the deposit has been contemporaneous 

 with the formation of the rock ; or that it occupies fissures in the 

 rock, which are now imperceptible, into which it was subsequently 

 conveyed by sublimation from the interior of the earth. — L'Instiiut, 

 No. 160. 



DONIUM, A NEW METAL CONTAINED IN DAVIDSONITE. 



This mineral was discovered by Dr. Davidson of Aberdeen, in a 

 granite quarry in the neighbourhood of that city ; it has been ex- 

 amined by Mr. Thomas Richardson, and he concludes that he has 

 obtained from it a metal which differs from any previously known. 



"From the alkaline and earthy bases, and from several of the 

 metallic ones, it is eminently distinguished by the green precipitate 

 which it gives with sulpho-hydrate of ammonia ; while its solubility 

 in the caustic alkalies, and in carbonate of ammonia, the light 

 brown precipitate thrown down by sulphuretted hydrogen, and the 

 green given by sulpho-hydrate of ammonia, are amply sufficient to 

 distinguish it from all the others. 



