Dr. R. D. Thomson, on the Analyses of Minerals. 99 



Phacolite, from Glenarm. — This mineral has usually been confounded 

 in this country with Levyine. Mr. Parry found it to yield, by two ana- 

 lysis, very carefully made — 



i. n. 



Silica, 4703 4785 



Alumina, 1947 1884 



Lime, 1074 950 



Potash, 118 166 



Soda, — trace. 



Water, — 2186 



This mineral loses from 3 to 4 per cent, of water in a vacuum. It may 

 bo readily distinguished from Levyine, by the character which the latter 

 possesses of intumescing before the blowpipe. 



Gismondine, from Mount Vesuvius, in small mamillary crystals, resem- 

 bling a dew-drop on the surface of volcanic rocks — analysed by Mr. Parry. 



Silica, 42-33 



Alumina, 2344 



Lime, 763 



Potash, 8*21 



Soda, 1-25 



Water, 1726 



The following minerals are not Zeolites. 



Brown Tourmaline from Perth, Upper Canada, was examined by Mr. 

 Parry : — 



I. II. HI. 



Silica, 3936 3768 3814 



Alumina, 2862 2868 29-54 



Protoxide of Iron, 1621 1804 1750 



Magnesia, 272 384 336 



Lime, 129 299 161 



Potash, ^.. — — 0-91 



Boracic acid, — — 362 



Volatile matter, — ~ 0*28 



Ilaphilite, or Grey Tremolite, from Canada, Sp. Gr. 287. 



I. n. 



Silica, 57*38 5681 



Lime, 1440 1481 



Alumina, 213 208 



Protoxide of Iron, 446 7'05 



Magnesia, 1600 16'80 



Water, — 242 



The first analysis was made by Mr. Clutterbuck, the 2d by Mr. Hugh 

 B. Tennent. 



