392 Off Metallic Titanium. — On Silicium and Zirconium. 



nected with each substance. Thus, here will be seen the diffe- 

 rent ores, as when first taken from the earth, and the same in 

 all the degrees of purification, &c. — the clays in all the stages 

 of manufacture — the substances used in colouring, in the ma- 

 nufacture of glass, &c. &c. 



Mineralogists throughout the country, it is hoped, will avail 

 themselves of the permission granted by the Corporation of 

 the University to exchange duplicate specimens. — Boston 

 Journal of Philosophy. 



ON METALLIC TITANIUM. 



Dr. Walckner of Freyberg, in the Breisgaw, has lately de- 

 scribed cubical crystals of metallic titanium which he ob- 

 served in iron-slags from the Upperland of Baden. The slag 

 was from a furnace where pea-ore (bohnerz) was smelted, and 

 analysis proved that this ore of iron contained a minute por- 

 tion of titanium. Dr.Wollaston*, as is well known, was the 

 first who described these cubes. They occur in the slags of 

 iron forges in Wales, in those at Bradford in Yorkshire, Al- 

 freton in Derbyshire, at Pontypool in Monmouthshire, in 

 Clydesdale in this country, and we have, no doubt will be met 

 with in many other places where our common iron-ores are 

 smelted. — Edin. Phil. Journ. vol. xi. p. 41 1. 



PROF. BERZELIUS ON SILICIUM AND ZIRCONIUM. 



In trying to reduce fluoric acid by potassium, I succeeded 

 in reducing silica, zirconia, and the other earths; but I have 

 only been able to separate silicium and zirconium. The others 

 decompose water with the greatest energy. Pure silicium is 

 incombustible even in oxygen gas. Water, nitric acid, or 

 nitro-muriatic acid, do not attack it, nor does caustic potash ; 

 but fluoric acid dissolves it a little, especially if nitric acid be 

 added. It does not decompose nitre, except at a very intense 

 heat, but it detonates with carbonate of potash at a dull red 

 heat ; carbonic oxide gas is liberated, and carbon is set at li- 

 berty. When it is heated with nitre, if a small piece of dry 

 carbonate of soda is introduced into the mixture, there is im- 

 mediate detonation. When the vapour of sulphur is passed 

 over silicium heated to redness, the metal quickly becomes 

 incandescent. When the combination is perfect, which sel- 

 dom happens, the substance is in the form of a white earthy 

 mass, and decomposes water with great rapidity. The si- 

 lica is dissolved, and sulphuretted hydrogen gas liberated. 

 By this means a solution of silica in water may be obtained, 

 * Sec Phil. Mag. vol. lxii. p. 18 ; lxiii. p. 15. 



SO 



