THE TECHNOLOGIST. [June 1, 1865. 



490 on magnesium. 



warranted in taking out his first patent for " Improvements in the 

 Manufacture of the Metal Magnesium." His success was at the same 

 time, attested by the circulation amongst his acquaintances of specimens 

 of the new metal from the size of a pin's head to that of a hen's egg. 



The metal in this state burnt freely enough, but it contained slight 

 impurities, and demanded further treatment to render it ductile and 

 malleable. Again Sonstadt set to work, and after another arduous series 

 of experiments, devised a process of purification by distillation, which he 

 secured by patent in May, 1863. One ol the first lumps of the distilled 

 metal was presented to Professor Faraday at the Royal Institution — the 

 spot where magnesium was first introduced to human knowledge. " This 

 is indeed a triumph ! " exclaimed the great philosopher as he poised the 

 shining mass in his hand. 



Not yet, however, had the time arrived for working magnesium on a 

 commercial scale. Many details had to be brought still nearer practical 

 perfection, and the summer and autumn of 1863 were consumed in 

 experiments. At last, with the close of the year, Mr. Sonstadt con- 

 sidered it safe to commence manufacturing. The Magnesium Metal 

 Company was organized, and operations commenced in Manchester. 



The aim with which Mr. Sonstadt set out was, a ready method for the 

 extraction of magnesium from its ore, and his merit is to be measured 

 by its achievement. The methods of his predecessors were only prac- 

 ticable in the laboratory, indeed, they made no pretence to practise else- 

 where ; they required complicated apparatus and delicate manipulation, 

 and, with all care, frequently resulted in failure. His method, on the 

 contrary, is so simple, that it can be accomplished by the hands of 

 ordinary workmen, and on a scale only limited by the convenient size 

 of vessels and furnaces. At Loughborough, at Midsummer, 1863, we 

 saw some pounds of magnesium made by a labourer and his boy with 

 perfect ease. 



The manufacture of magnesium, as conducted in Manchester, may 

 he conveniently described under three heads : — I. The preparation of 

 anhydrous chloride of magnesium. II. The release of the magnesium 

 from the chlorine. III. The purification of the magnesium by distilla- 

 tion. 



I. Lumps of rock-magnesia (carbonate of magnesia) are placed in 

 large jars and saturated with hydrochloric acid. Chemical action at 

 once ensues ; the union of carbon and oxygen with magnesium in the 

 rock is dissolved ; the magnesium combines with the chlorine of the 

 acid, forming the desired product — chloride of magnesium, but in solu : 

 tion. 



The water is next evaporated from the salt. The liquor is poured 

 into broad open pans, which are placed over stoves. When the drying 

 is sufficiently advanced, the salt is collected into a crucible and sub- 

 jected to heat until perfectly melted and the last traces of water driven 

 off, when it is stowed away in air-tight vessels. 



