136 



VOLCANIC ROCKS— SANDWICH ISLANDS. 



Uppee 



GrALLEUY. 



Wall-case 1. 



SO.— Very vesicular lava, or cellular obsidian. 

 31. — Scoriaceous lava, enclosing frag-ments of 





lar lava. 



vesicu- 



R9 



Finely vesicular basaltic lay a. 



33. — Compact basaltic lava. 



• 



34.— Vesicular lava, coated with gypsum {sulphate of 

 lime), which also fills some of the cells. 



35. — Scoriaceous lava, with crystals of specular iron. 

 36. — Vesicular lava, or cellular obsidian, containing 



olivine. 



37. — Basaltic lava, with crystals of augite, some of 

 which are in a decomposed state. 



37a. — Compact basaltic lava, with crystals of augite, 

 mostly in a decomposing state, and minute brilliant octohe- 

 dral crystals of specular iron. 



38. Augitic lava, scoriaceous, and containing crystals 

 of olivine. 



39. — Vesicular lava, with olivine. 



40. — Scoriaceous augitic lava, with crystals of augite. 

 41. — Scoriaceous lava, with large crystals of augite and 



olivine. 



42. 



K\ 



42 a. — Native sulphur, sublimed round the twigs of 



plants. — Kilauea. 



The presence of Selenium in the sulphur from Kilauea 

 has been determined by the analysis of Professor Siliiman. 



Specimens of the igneous rocks of the mining districts of 

 Schemnitz, Hungary, the Bannat, Croatia, and Tran- 

 sylvania. 



Presented by Warington W. Smyth, M.A., F.G.S. 



" The Hungarian lavas are chiefly felspathic, consisting 

 of different varieties of trachyte ; many are cellular, and 



* 



used as millstones ; some so porous, and even scoriform, as 

 to resemble those which have issued in the open air. 

 Pumice occurs in great quantity ; and there are conglo- 



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