14 GEOLOGICAL MEMOIRS. 



substance ; the principal mass of the rock offering considerable re- 

 sistance to the altering agents, as may be seen in the steep decUvities 

 and in the columnar sharp-edged peaks around Carlsbad. The sur- 

 face of these rocks is full of cavities marking the places of the iso- 

 lated felspar-crystals now decomposed. 



The varieties a and b are less liable to be divided by fissures, 

 caused by atmospheric agency, into masses with plane surfaces and 

 sharp edges than is the variety c. The River Tepl, as far as it runs 

 through the variety c, follows exactly the direction of these clefts or 

 fissures. When basaltic eruptions, very probably immediately con- 

 nected with the origin of the thermal springs, disturbed the rock- 

 masses of the Carlsbad territory, the deepest fissures, it is considered, 

 must necessarily have been formed in the variety c, on account of its 

 lithological constitution and the mode of its Assuring. This supposi- 

 tion may serve to explain why all the springs issue from the fissure 

 in the variety c. There is nothing to confirm the idea of a difference 

 of age among the granites ; which is indeed rather contradicted by 

 the insensible transitions from one variety into another, and by the 

 presence of tin-ore in all the granites, even in and around Carlsbad. 



Dr. Hochstetter distinguishes his three varieties of Carlsbad granite 

 by special names ; variety a is his " Kreutzberg granite ; " var. b is 

 his " Elbogen granite ;" and var. c his " Carlsbad granite." A map 

 of the territory of Carlsbad, by the author, on the scale of xttto* 

 is preparing for publication. [Count M.] 



1 



On PiANziTE/rom Styria. By Dr. Kenngott. 



[Proceed. Imp. Geolog. Institute of Vienna, January 8, 1856.] 



This mineral was first described by M. Haidinger in 1844*, as 

 a new species of fossil bitumen, to which he assigned the name of 

 Pianzite, indicative of the locality where it was first discovered. It 

 occurs at Mount Chum, near Tuffer, in Styria, under the same cir- 

 cumstances as at Pianze in Carniola. This new locality has been 

 made known by Che v. Pittoni de Dannenfeldt, of Gratz. 



According to the communications of M. Wodiczka, Imp. Mining 

 Inspector at Cilli, the pianzite occurs, though only in small lumps 

 and very thin layers, in nearly all the mines by which the carboni- 

 ferous strata running westward from Tuffer, over Goufe and Hrast- 

 nigg, to Trifail and Sagor, are at present worked. Near Tuffer, 

 3000 Vienna pounds (3702 pounds avoirdup.) of this substance have 

 been brought to day. 



The pianzite is a black resin, much resembling slaty and lamellar 

 black coal ; its texture, never crystalline, varies from compact to 

 lamellar or scapiform ; its colour when scratched is light-brown. It 

 melts into a black mass, similar to pitch, at a temperature exceeding 



* Poggendorff's Annalen der Physik und Chemie, vol. Ixii. p. 275. 



