458 RECORD OF SCIENCE FOR 1886. 



crystals are sbown to be compound in nature. The axial ratio obtained 

 isrt : b : c=0.aS43 : 1 : 0.4213; the prismatic angle is 119^ 2-4'. An anal- 

 ysis of the best material available yielded uncertain results because of 

 the admixture of percylite. A definite composition is obtained only 

 alter a series of assumptions, which impair the reliability of the result. 

 The caracolite and i)ercylite are taken as i^reseut in about the ratio of 

 G : 1, and the final formula given for the former is rbClHO+Na2S04, 

 which demands : 



PI) Na 01 s H o 



51.56 11.46 8.84 7.07 0.25 19.92 = 100 



In view of the remarkable nature of the compound a further exam- 

 inatinn of purer material is needed. 



DognacsJcaite. — Briefly mentioned by Krenuer as a sulphobismuthite 

 of copper, occurring at Dognacska, lu Hungary. It is massive, with a 

 .single perfect cleavage, and becomes gray or brown on exposure to the 

 air. An analysis by Maderspach yielded S 15.75, Bi 71.79, Cu 12.2S. It 

 is associated with gold, pyrite, chalcocite, and bismite. 



Emmonsite. — A ferric tellurite from the neighborhood of Tombstone, 

 Arizona, uamed by W. F. Ilillebraud after S. F. Emmons, of the U. S. 

 Geological Survey. It occurs iu translucent crystalline scales of yel- 

 lowish-green col r imbedded in a hard brownish gangue, consisting of 

 lead carbonate, quartz, and a brown substance containing the hydrated 

 oxides of iron and tellurium. The crystallization is regarded as prob- 

 ably monoclinic; the specific gravity is about 5. The result of several 

 analyses, after impurities had been deducted, gave: 



Te Se Fe H2O 



58.75 0.53 14.29 uudetermined. 



The conclusion reached is that the mineral is a ferric tellurite, but 

 the formula is doubtful, and it needs further examination, based on purer 

 material. A related, but according to Dr. Smith, a distinct species is 

 his ferrotellurite. 



Harsfujite. — A new silicate of calcium, aluminium, and manganese, 

 from Pajsberg, Sweden, named and described by G. Fliuk. It occurs 

 with garnet rnd rhodonite in small prismatic crystals, haviuga prismatic 

 angle of IO90 11'. The axial ratio is, d'.h: c=0.7141 : 1 : 1.01495; the 

 habit is something like that of chrysolite. No cleavage was observed. 

 The hardness is 5.5, the fracture small conchoidal or splintery, the spe- 

 cific gravity 3.049. It is colorless, with vitreous luster. The optic axial 

 plane is parallel to the brachypinacoid, and the axial angle in air is 

 9()o 27' for yellow light. An analysis yielded: 



SiOa AI2O3 C.1O MuO FiO MgO K2O NajO H2O 



38.94 10.01 29.23 12.81 U: 3.27 0.35 0.71 3.97 = 99.89 . 



