Scientific Intelligence. — Geology. 187 



year, whereas, on the Continent, they are much scarcer, and are 

 hardly ever met with in the southern part of Siberia — Wrangell, 

 p. 185. 



10. Dysodolite. — This mineral, arranged in systems of mineralogy 

 under the name Foliated Mineral Pitchy Ehrenberg has shewn to 

 consist of bitumen, or mineral pitch, mixed with siliceous shells of 

 infusoria, and occasionally with pollen of pines, &c. The wax- 

 yellow variety found in Sicily is made up of shells of navicula and 

 mineral pitch : the nearly black-brown coal of the Westerwald is a 

 variety of dysodolite, so also is^^the foliated leather-like bituminous 

 coal of the Gesteinger Busch at Rott and Siegburg in the Sieben- 

 gebirge, and a foliated brown coal from the Vogelsberge. Hence 

 the mineral species named dysodolite appears to be a poller slate, 

 impregnated with bitumen. Its colours are black, brown, or black. 

 It never forms very thick beds, but sometimes widely spread de- 

 posits. It is used as fuel. 



11. Pihlite, a New Mineral. — Sefstrom has discovered at Fahlun 

 a new mineral, which replaces niica in granite, and which he has 

 termed Pihlite in honour of the late M. Pihl, director of mines. 

 It is an intermediate substance between talc and mica, and its com- 

 position is expressed by the following formula : 



— BerzeliuSy in Leonhard and Broun s Jahrbuch. 



12. PyrrhitCy a New Miner aL — Only one example of this sub- 

 stance is known, and occurs in a splendid drusy cavity of felspar, 

 which is in the possession of Vice-President Perowski of Peters- 

 burgh. While the cavity chiefly contains felspar crystals several 

 inches in size, finely defined, and of an ochre-yellow colour, it 

 likewise includes six-sided tables of reddish-white, pearly lithion 

 mica ; white translucent crystals of albite ; crystals of clove-brown 

 rockcrystal; and a i^\Y white topazes. The crystals of the new 

 mineral are superimposed on the felspar, are eight in number, and 

 are octahedrons of about three lines in length. Their surfaces are 

 smooth, but possess little lustre, so that their angles cannot be mea- 

 sured with great accuracy ; but, from observations made on several 

 angles, the mean may be regarded as 109° :>8', so that we may pro- 

 bably assume that the crystals are regular octahedrons. No clea- 

 vage is observable. The colour is orange-yellow, and the lustre 

 feebly vitreous. The substance is translucent on the edges ; its 

 hardness is that of felspar, but the specific gravity could not be de- 



