380 Scientific Intelligence — Mineralogy. 



16. Analysis of Pyrophyllite of Spaa. By M. Rammehberg 

 (Pogg. Annalen, Ixviii., 505). — The analysis afforded, silica 66-14 

 alumina 25-87, magnesia 1-49, lime 0-39, water 5-59 = 99-48. 



17. Analysis of Talc of Rhode Island and Steatite of Hungary. 

 By M. A. Delesse (Rev. Sci. et Indust., xxv., 107). — The talc of 

 Rhode Island occurs in large clear foliated masses. It has two 

 optical axes intersecting at a small angle ; density = 2-5657 ; after 

 calcination = 1-64. Hardness = 1 ; after calcination = 6, so that 

 it scratches glass, although with some difficulty. It exfoliates when 

 heated. On analysis it afforded silica 61 -75, magnesia 31-68, protoxide 

 of iron 1-70, water 4-83 = 99-96. 



18. On a new Hydroiilicate of Alumina. By MM. Damour 

 and Salvetat {Ann. de Ch. et de Ph., Se Ser., xxi., 376). — This 

 mineral occurs massive in nests in a brownish clay near Montmo- 

 rillon (Vienna). It has a soapy feel, and a pure rose colour, and 

 becomes ^plastic in water. Composition, according to Damour, 

 silica 50-04, alumina 20-16, sesquioxide of iron 0-68, limej,l-46, 

 potash 1-27, magnesia 0-23, water 26-00. It is hence allied to 

 Halloysite. 



19. Philippsite and Gismondine. By M. Marignac {Ann. de 

 Ch. et de Phys., 3e ser., xiv.. 41). — Marignac separates these spe- 

 cies, which Kobell and Brooke had united. Under Gismondine he in- 

 cludes specimens having an octahedral form, and rarely mammillated, 

 and faces not striated ; and under Philippsite, those whose crystals 

 have a rectangular prismatic form terminated by a four-sided pyra- 

 mid, with the faces striated in two directions oblique to one another. 

 Density of Gismondine 2-265, of Philippsite 2-213. 



20. On the Composition of Heulandite. By M. Damour (Comp- 

 tes Rendus, xxii., 926 ; Annuaire de Chim., 1847). — Damour has 

 detected in Heulandite a portion of soda and potash which simplifies 

 the formula. His analysis gives, silica 59-64, alumina 16-33, 

 lime 7-44, soda 1-16, potash 0-74, water 14-33 = 99-64. Hence, 

 this mineral differs from stilbite only in the proportion of water. 



21. On the Identity of Osmelite and Pectolite {Annuaire de 

 Chem., 1848, p. 166). — An analysis by M. Adam indicates that 

 osmelite of Breithaupt is identical with Kobell's pectolite. It con- 

 tains, silica 52-91, lime 32-96, protoxide of manganese 1-44, soda 

 6-10, potash 2-79, alumina and oxide of iron 0-54, water 4-01. 



22. On Bisterrite, from the Valley of Fassa in Tyrol, By M. 

 Von Kobell {Jour. of'Prak. Ch., xli, 154; Annuaire de Ch., 

 1848, 173). — Disterrite crystallizes in hexagonal prisms, cleaving 

 parallel to the base, and has a pearly lustre on the terminal faces, 

 with a vitreous lusti-e on the sides of the prism. H = 5 to 62 

 (Breithaupt's scale) ; sp. gr. 3-042 — 3-051 ; Composition, silica 

 20-00, alumina 43-22, peroxide of iron 3-60, magnesia 25-01, 

 lime 4-00, potash 057, water 3-60. 



23. On Glaucophane. By M. Hausmann {Jour, of Prak. Ch., 



