458 Cambridge Philosophical Society. 



second is inclined at an angle of 153°, and the third at an angle 

 of 133°. The specimen transmitted to me is intermixed with 

 pyrite and baryte. 



I found the specific gravity to be = 6*920. Its behaviour 

 before the blowpipe and in the moist way resembles that of patri- 

 nite. Decomposed by means of chlorine, it gave the following 

 result : — 



Sulphur 18-00 



Bismuth 60*95 



Lead 16*73 



Copper 2-42 



Iron 1*02 



Silver trace 



Insoluble 0*59 



99-71 



Calculating for the separate metals what are the requisite 

 amounts of sulphur, we obtain — 



13*80=74*75 Bi^S^ 



2*60"lo 91=19-33 PbS rq 



0*61/^*'^ = 3*03 Cu^S T 



1-21= 2-23 FeS2 J> 



18*22 

 After deducting the inconsiderable amount of the intermixed 

 pyrite, the quantity of sulphur contained in the PbS (Cu^S) and 

 the Bi^ S^ affords the ratio of 1 : 4|, so that the formula for this 

 new compound is — 



The mineral, the name for which is derived from its locality, 



therefore approaches patrinite, which is 3 ■< p go [^Bi*S^. Ko- 



bellite contains 3PbS, Bi* S^, and Klaproth's cupreous bismuth 

 from Wittichen is perhaps 2Cu^S, Bi'^ S^. 



— — T^" - 



tXXIII. Proceedings of Learned Societies. , j 



CAMBRIDGE PHILOSOPHICAL SOCIETY. '^^ 



[Continued from vol. iii. p. 317.] ,^^^ 



Feb. 16, PROFESSOR MILLER made a communication on the 

 1852. ^ Artificial Formation of Crystallized Minerals. 

 March 1. — Mr. Hopkins, F.R.S. &c., gave a Lecture on the In- 

 fluence of Internal Heat, Stellar Radiation, and Configuration of 

 Land and Sea in producing Changes of the Earth's Superficial Tem- 

 perature. 



