CHEMICAL SCIKXCE. 279 



THE METAL MAGNESIUM. 



MM. Dcvillc and Caron, have communicated to the Comptes Eendus 

 the following information respecting the Metal Magnesium : 



The chemical properties of magnesium have been determined with extreme 

 perfection by M. Bussy, to whom we owe the discovery of this metal. There 

 exists, however, in this metal a physical property which has, as yet, been 

 overlooked ; it is a new fact in which it resembles zinc, to which it was already 

 so closely allied. Magnesium is volatile like zinc, and nearly at the same 

 temperature. Thirty grammes (about one ounce) have been distilled easily 

 at a time. AYhen the magnesium is pure it leaves no residue, and the sub- 

 limed metal is white, surrounded with a small quantity of oxide. When it 

 is impure it leaves a certain amount of very light black matter of a compli- 

 cated nature, and then the distilled magnesium is covered over with small 

 needle-shaped crystals, which are colorless and transparent, and which soon 

 decompose of their own accord into ammonia and magnesia ; this action in- 

 dicates the probable existence of a nitricl of magnesium, analogous to those 

 remarkable bodies which TV"ohler and Rose have already discovered in a cer- 

 tain number of simple bodies. 



Magnesium fuses at a temperature close appi'oaching that at which zinc 

 fuses. At a little higher temperature it burns with a dazzling flame, in the 

 midst of which can be observed, from time to time, tufts of an indigo blue 

 tint, more especially if it is burned in a jet of oxygen. The combustion of 

 the magnesium is accompanied with all the phenomena observed in the com- 

 bustion of zinc, and which denote a volatile metal, of which the oxide is fixed 

 and infusible. 



The density of magnesium was found to be equal to 1'75 ; it can be filed 

 very well, and burnishes beautifully ; it keeps very well in the atmosphere 

 when it is pure and its surface polished, but is scarcely equal to zinc in this 

 respect. 



Six hundred grammes of chloride of magnesium, prepared by the ordinary 

 process, but with great care, are mixed with about one hundred grammes of 

 chloride of sodium, which has been previously fused, or a mixture of the 

 chlorides of sodium and potassium and one hundred grammes of pure fluoride 

 of calcium ; these arc all in powder. To these are added, in small pieces, 

 one hundred grammes of sodium, and the whole, mixed intimately, is thrown 

 into an earthenware crucible at a red heat, and afterwards covered with a lid. 

 In a short time the action begins, and when the noise ceases the crucible is 

 uncovered, and the melted mass stirred by means of an iron rod until it ap- 

 pears homogeneous ; globules of magnesium are now observed, and the 

 crucible is taken from the fire to cool. When the saline mass is about to 

 congeal it is again agitated, and all the small particles of metal spread over 

 it arc gathered together by means of the iron rod, and formed into one piece, 

 which is drawn on a plate of iron. The scoria or slag mav be fused over 



ti 



again, once or even twice, and each time a small quantity of the metal is 

 obtained from it. Six hundred grammes of chloride of magnesium acted 



