148 



[Senate 



natural size in his possession. It is a flattened cube. The lateral 

 planes P P", as well as the replacements of the lower solid angles a, 

 are extremely brilliant and regular ; but the upper solid angles and the 

 terminal edges, are replaced by planes, which successively rise, in a 

 step-like manner to the apex, forming a low pyramid. See his explana- 

 tion of the mode of formation, Phillips^ Mineralogy, Suppl.^ p. 623. 



WHITE LEAD GEE. 



(Mineralogy of New- York, page 414.) 



Small crystals of carbonate of lead, an eighth of an inch or less in 

 length, are occasionally found sprinkled thickly over the surface of the 

 galena of Rossie, which when this is the case is deeply roughened or 

 corroded. The crystals are striated prisms, terminating in four bril- 

 liant planes, two of which meet at an angle of 117^ nearly, and the 

 other two at an angle of 88°. The crystalline form, as well as the 

 blowpipe characters prove that the mineral is carbonate of lead. Dr. 

 G. Hadley, in Sill. Jour., Jan., 1847. 



NATIVE COPPER. 

 (Mineralogy of New- York, page 420.) 



Prof. Dewey states that he has found some speculae of native copper 

 ^n the pentamerus limestone, (probably near Rochester, Monroe county.) 

 Pyritous copper and green carbonate of copper occur in the same mass. 

 HaWs Rep. mi Geol., ^th List., p. 67. 



This mineral is also occasionally found in the Taconic slate. JEm- 

 mons^ Rep. on Geol., 2d Dist., p. 15S. 



RUTILE. 



(Mineralogy of New- York, page 428.) 



According to Damour, this mineral is identical in composition with 

 anatase. Phil. Mag. ^ A7in., xxiv., p. 477. 



SPHENE. 



(Mineralogy of New- York, page 433.) 



A brown mineral resembling sphene, but supposed to be different, is 

 said to have been found in Rossie, St. Lawrence county. Emmons^ 

 Rep. on Geol., 2d Dist., p. 366. 



Sphene has been found in Putnam Valley, Putnam county, by Mr. 

 Cyrus P. Fountain. 



