600 MANUAL OF NATURAL HISTORY. 



blue, sub- transparent, sp. gr. 2 -21, or " Blue- 

 Vitriol, " and many other less important forms. 

 Found in Siberia, at Fahlun in Sweden, in 

 Cornwall, in Australia, and in various parts 

 of America. Symb. Cu. 



4. FAMILY. Ammoniides. Minerals containing 



compounds of Ammonium. Occur 1, as Oxide 

 or "Ammonia," in small quantities in the 

 atmosphere, smell pungent ; sp. gr. - 0'589 ; 

 2, as Chloride or "Sal-ammoniac/" as an 

 efflorescence; H. = 1-5-2, sp. gr. = T52; 

 whitish ; 3, as Sulphate of Ammonia or 

 " Mascagnine/' about volcanoes ; 4, also as 

 Phosphate, Bicarbonate, and combined with 

 with Phosphate of Soda or " Salt of Phos- 

 phorus \" compounds of Ammonium vola- 

 tize with heat, when triturated with mois- 

 tened Hydrate of Calcia (lime) ammonia is 

 given off. Symb. Am. 



5. FAMILY. Natrides. Minerals containing com- 



pounds of Sodium. Occur 1, as Sulphate, or 

 "Glauber-Salt," in right prisms, H. 1-5-2, 

 sp. gr. 1-481, white, efflorescent, in thermal 

 springs, &c. ; 2, with Sulphate of Lime, as 

 " Glauberite," in oblique prisms, H. 2*5-3, 

 sp. gr. 28, gray, brittle, with rock-salt ; 3, as 

 Nitrate, or "Soda Nitre/' rhombohedral, 

 H. l'5-2, sp. gr. 2*1, white, efflorescent, in 

 Chili ; 4, as Chloride, or " Common Salt/' 

 cubical, H. 2'5, sp. gr. 2'25, white, somewhat 

 brittle and deliquescent, in the ocean, in some 



