244 ANNUAL OF SCIENTIFIC DISCOVEEY. 



principal associated minerals are the red, green, blue and black tour- 

 malines, lepidolite in large masses, mica, beryl, amblygonite yttrocerite, 

 brookite and zircon. These all occur disseminated through a wide 

 vein of albite and feldspar, with some other more common minerals. In 

 Hebron, about eight miles from this locality, there is another vein con- 

 taining nearly the same minerals, except perhaps the last three, which 

 have not yet been noticed ; and, in addition, mispickel. Tin ore was 

 found here by Prof. Brush in small crystals. These localities will per- 

 haps serve as an indication of the manner in which this ore may occur 

 at other places in New England. 



Cryolite. This interesting mineral, which a few years since was 

 only looked upon as a mineralogical rarity, has now become an impor- 

 tant article in commerce. Aside from its use as a source of aluminum 

 as suggested by Percy and H. Rose, we learn from recent articles in 

 Dingier' s Polytechnisches Journal, that it is now extensively employed 

 in chemical works at Copenhagen and Harburg for the production of 

 caustic soda and salts of alumina. 



J. Thomsen claims to have discovered in 1850 that cryolite could be 

 decomposed by lime and lime salts ; and after perfecting his process, he 

 commenced the manufacture of soda in 1857, and in 1858 erected large 



*3 



works at Copenhagen which now use 40,000 cwt. of cryolite annually. 

 The exploration of the cryolite deposit in Greenland has become so ex- 

 tended that another large manufactory has been erected at Harburg, 

 and others are being put up at Prague, Selicie and Mannheim. It is 

 estimated that these manufactories will consume from 120,000 to 150,- 

 000 cwt. (6000 to 7500 tons) of cryolite annually. Cryolite is de- 

 livered at Harburg for about two dollars per cwt. Sittiman's Jour- 

 nal. 



Natural Formation of Carbonate of Soda. Prof. R. Haines, of 

 Bombay, has communicated to the London Pharmaceutical Journal a 

 note relating to a substance found all along the coast to the east of 

 Aden, to an extent of perhaps ten miles, and in quantity, practically, 

 unlimited. It is usually obtained in hollows behind or beyond high- 

 water mark, to which sea-water has access by percolation. The only 

 use made of it was to mix with snuff to give it pungency, and also, but 

 rarely, to wash clothes. Prof. Haines describes this substance as con- 

 sisting of " irregular, nearly colorless, partly crystalline masses, of a 

 greasy feel, and rather strong, soapy odor, very similar to that of crude 

 borax. The chemical analysis gave neutral carbonate of soda, 

 51.05 ; common salt, with traces 'of sulphate of soda and chloride of 

 magnesium, 24.94; water and organic matter, 19.66; sand, 4.35. A 

 writer in a later number of the Pharmaceutical Journal also adds : 

 From a paper recently published by Mr. H. J. Carter in the Transac- 

 tions of the Royal Asiatic Society, on the geology of Arabia, it appears 

 that the whole of the southeast coast of Arabia is capped with num- 

 mulitic limestone, pierced at frequent intervals with basaltic effusions, 

 and in many places elevated so as to form lofty and abrupt cliffs, in 

 which, beneath the limestone, other formations are visible. As a re- 

 sult of this formation, the shingle on the coast consists mainly of lime- 

 stone ; and although no specific description of the coast immediately 

 to the east of Aden has been given, there is no reason to doubt that 

 the same peculiarities prevail there. It is then to the percolation of 



