Intelligence and Miscellanies. 



389 



the tongue, amorphous and appears to be composed al- 

 most entirely of pure silica and water. — Ibid. 



20. Analysis of Tourmalines.^ — M. Gmelin divides the 

 tourmalines into three groupes. 



1. Tourmalines which contain lithia. 

 alysed three varieties : — I. Tourmalines 

 via : Sp. Gr. 2-96 to 3-02. II. Red Tourmaline of Perm in 

 Siberia: Sp. Gr. 3-059 to 3-10. III. Tourmaline of a ce- 

 landine green color, from Brazil : Sp. Gr. 3-079. 



Of these he has an- 

 of Rosna in Mora- 



2. Tourmalines which contain potash or soda, or both, 

 without lithia, and without a remarkable quantity of magne- 

 sia. The following specimens have been analysed : — I. 

 Black tourmaline of Bovey in Devonshire: Sp. Gr. 3-246. 



II. Black tourmaline of Eibenstock in Saxony.' Sp. Gr. 3-123. 



III. Green tourmaline of Chesterfield, North America : Sp. 

 Gr. 3-102. 



* A notice of the analysis of tourmalines, by Gmelin, was published in Vol. 

 XIV. page 385, but without the tables, which present the results in a very 

 striking form. 



