1819.] Scientific Intelligence. 69 



Although they resemble the cubic zeolite, yet they have nothing 

 of its character with them besides." 



VI. Native Carbonate of Magnesia. 



This mineral species was discovered a good many years ago 

 by Dr. Mitchell, of Belfast, in a serpentine rock at Hrubschitz, 

 in Moravia. It has been recently discovered by Mr. James 

 Peirce, at Hoboken, in Staten Island, on the New Jersey side of 

 the Hudson, the very same place where the hydrate of mag- 

 nesia was discovered by Dr. Bruce. The carbonate of magnesia 

 occurs in a serpentine rock, in horizontal veins, about. two inches 

 in thickness. When first taken out, it was soft, white, and very 

 slightly adhesive from a little moisture ; but when dry it fell to 

 powder with friction. It was totally soluble in sulphuric acid 

 with effervescence, and yielded crystals of Epsom salt. Mr. 

 Peirce did not ascertain the proportion of carbonic acid which it 

 contained ; but from Bucholz's analysis of the native carbonate 

 of magnesia found in Germany, we learn that it is a compound 

 of one atom carbonic acid and one atom of magnesia ; or by 

 weight of 



Carbonic acid 2-75 52-38 



Magnesia 2-50 47-62 



5-25 100-00 



There can be little doubt that the composition of the American 

 carbonate of magnesia will be similar. 



More lately Mr. Peirce discovered in the same place veins of 

 native carbonate of magnesia in fine acicular crystals. The 

 discovery was made during the examination of an excavation 

 dug about three miles from the Quarantine under the delusive 

 expectation of finding gold. The native carbonate of magnesia 

 was observed in very white acicular crystals, grouped in minute 

 fibres, radiating from the sides ; but not always filling the veins 

 and cavities in which it was found. The crystals were in some 

 instances suspended, assuming a stalactitical form. — (Silliman's 

 Journal, i. 54 and 142.) 



VII. Picromel. 



This is a name given by Thenard to the peculiar substance to 

 which ox bile is indebted for its properties. Berzelius first 

 pointed out an easy method of procuring it. Sulphuric acid 

 throws it down in the state of a green resinous-looking matter, 

 which used formerly to be denominated resin of bile. If we put 

 this matter along with a quantity of carbonate of barytes in 

 powder into a flask or retort containing a sufficient quantity of 

 distilled water, and place the vessel upon a sand-bath, the sul- 

 phuric acid gradually unites with the barytes, and the picromel 

 being set at liberty dissolves in the water. We have only to 



