Scientific Intelligence. — Mineralogy/. 187 



Mll^ERALOGY. 



5. optical Property of Dichroite. — This mineral, which in 

 interesting, not only on account oi' the different colours it ex- 

 hibits in common light, but also in polarised light, has been 

 found, by Professor Marx, to possess, like tourmaline, the pro- 

 perty of polarising light itself. 



6. Ilmenite of Siberia is Polygmite, — Among the minerals 

 brought from the Urals, Professor Kupfer of Kasan observed 

 one which he at first took for tantalite, but afterwards ascer- 

 tained to be a particular species, to which he gave the name 

 Ilmenite, from the Ilmen mountains in the Urals, where it oc- 

 curs. The following are its characters : — Colour black, streak 

 brownish. Occurs massive, rarely crystallised, in variously mo- 

 dified, oblique four-sided prisms ; therefore belongs to the pris- 

 matic series of Mohs. Lustre on the fracture shining and 

 resinous ; fracture conchoidal ; no cleavage visible ; fragments 

 sharp-edged ; opaque ; hardness = 4.0 ; specific gravity = 4.75 

 — 4.78. Kupfer is now disposed to consider this mineral as 

 identical with the polygmite of Berzelius. 



7. Scheererite, a new Mineral Species. — This mineral, 

 which belongs to the inflammable class, occurs near to St Gal- 

 len, in Switzerland, in a bed of brown coal. It was sent to 

 Professor Stromeyer, by Captain Scheerer of St Gallen. It 

 is found in loosely aggregated, whitish, feebly shining, pearly 

 crystalline grains and folia, that generally occur in nests in 

 brown coal. It is rather heavier than water ; does not feel 

 greasy, is very friable, has no sensible taste ; in the cold, and 

 even by friction, exhales no particular smell, but by heating 

 gives out a feeble aromatic empyreumatic smell. It melts very 

 readily into a colourless liquid. It becomes fluid at 86° R. In 

 this state it resembles a fatty oil, penetrates paper in the same 

 manner, but the spots or stains thus produced, disappear on the 

 paper being heated. The melted mineral, on cooling, crystal- 

 lises into four-sided acicular crystals. It inflames in a platina 

 spoon, held over a spirit of wine lamp, and burns with a feeble 

 aromatic-empyreuniatic smell, without leaving any residuum. 

 The preceding, and other properties, as given by Stromeyer, 

 go to prove, that Scheererite, like the Naphtaline, is a binary 

 compound of hydrogen with carbon. 



