1824.] Scientific Notices — Mineralogy. 315 



Huron ; gryphsea (lias), from Lakes Superior and Simcoe, area 

 (lias), Lake Simcoe, and sanguinolaria, River Humber, Lake 

 Ontario." — (American Journal of Science.) 



J 2. Analyses of Chrysobcrylsfrom Haddam, in Connecticut, V. S. 

 and Brazil. By Mr. H. Seybert. 



The Haddam chrysoberyl occurs in a coarse-grained granite, 

 in which the predominating ingredient is albite, and is asso- 

 ciated with greyish-quartz, manganesian garnet, and beryl. The 

 mineral was extremely refractory when fused with caustic potash, 

 an effect ascribed by Mr. Seybert to the glucina being mixed 

 with a very small portion of titanium. He succeeded in effecting 

 its decomposition by repeatedly fusing it with caustic potash, 

 and when the alkali had no further action, calcinino- the resi- 

 duum several times with nitrate of barytes. His results °ive its 

 composition as follows : 



Moisture 0-40 



Oxide of titanium LOO 



Glucina 1 5*80 



Silica 4-00 



Alumina 73-60 



Protoxide of iron 3-38 



98-18 

 Loss 1-82 



100-00 



Mr. Seybert found the chrysoberyl from Brazil to consist of 



Water 0-666 



Oxide of titanium 2-666 



Glucina 16-000 



Silica 5-999 



Alumina 68-666 



Protoxide of iron 4-733 



Loss 1-270 



100-000 

 (American Journal of Science.) 



13. Description and Analysis of Sillintanile, a new Mineral 

 from Saybrook, in Connecticut, U. 6'. By Mr. G. T. Bow en. 



This mineral has been mistaken for anthonhyllite, and is so 

 called in the last edition of Cleaveland's Mineralogy. Its 

 colour is dark grey, passing into clove brown. It occurs in a 

 vein of quartz, penetrating gneiss, crystallized in rhomboidal 

 prisms, whose angles are about 106° 30' and 73° 10'; the incli- 

 nation of the base to the axis of the prism being about 113°. If 



