1865.] Mining, Mineralogy, and Metallurgy. 687 



ments which they think are confirmatory of the views entertained by 

 M. Marguerritte. They suppose the carburet of iron to be a definite 

 compound, which is infinitely soluble in melted iron. Many of the 

 experiments certainly appear to support this view, but there are many 

 reasons why we hesitate to accept this explanation as the decision of 

 a complicated problem. 



M. Troost has interested the Academy of Sciences at Paris by 

 an account of the process by which he has succeeded in obtaining the 

 metal Zirconium. It will be remembered, by most of our readers, 

 that the delicately tinted gem, the hyacinth Zircon, commonly called 

 the jargon, contains this metal, which was separated by BerzeHus, but 

 which has not, before the experiments by M. Troost, been produced 

 in a coherent form. By heating the double fluoride of Zirconium and 

 potassium with one part and a half of aluminium, to a temperature 

 required for melting iron, in a crucible made of gas retort charcoal, 

 crystalline laminae of Zirconium are formed around the button of 

 Aluminium. From these the Aluminium can be removed by means 

 of diluted Hydro-chloric Acid. 



The pure metal thus obtained is a very hard substance of the 

 colour of antimony, and much resembling it in lustre and brittleness. 

 The density of crystallized Zirconium is 4 • 15 ; it is not attacked by 

 either Sulphuric or Nitric Acids at ordinary temperatures, but is 

 readily dissolved by Hydro-fluoric Acid. It is a bad conductor of 

 electricity. M. Troost is still continuing his investigations, and we 

 may therefore. expect to know more of this rare and curious metal in 

 a short time. 



Our French neighbours boast of a new application of centrifugal 

 force. Iron tubes are now made by calling this power into play. 

 Into a cylinder of the required size, closed at each end, the necessary 

 quantity of melted iron is poured, and a rapid motion is communicated 

 to it. The melted metal is pressed against the sides of the cylinder ; 

 it cools while in motion, and the result is a perfectly uniform and 

 straight tube. The machine is invented by a young workman named 

 Auguste Larson, and the writer says* that the first trials are perfectly 

 successful. For many years a similar process has been employed in 

 this country, especially for small ornamental castings. The cylindrical 

 casings of the oil vessels of the Moderator Lamps have been so made. 

 The melted copper or bronze is poured into a cylindrical mould, 

 which, being closed, is allowed to roll down an incline plane ; here 

 centrifugal force is called into play, and remarkably sharp castings 

 are the result. 



A very important experiment is about to be tried, on a sufficiently 

 large scale, to determine its commercial value, by Messrs. Vivian and 

 Sons, of Swansea. The " copper smoke " so called, which envelopes 

 the town and destroys the vegetation in the valley and on the hills 

 around it, is produced by the volatilization of sulphur from the 

 copper ores which are smelted in the numerous and extensive works 

 which are located on the margin of Swansea Bay. An eminent 



* ' Lcs Mondes,' 20th July, 1865, p. 168. 



