162 THE CANADIAN NATURALIST. [Vol. vi. 



to be a success, and I am glad to be able to state that Mr. Deacon 

 has recently overcome certain difficulties in his method, and has 

 obtained a complete absorption of the chlorine. May we hope to 

 see oxygen prepared by a cheap and continuous process from at- 

 mospheric air ? With baryta the problem can be solved very per- 

 fectly, if not economically. Another process is that of Tessier de 

 Mothay, in which the manganate of potassium is decomposed by 

 a current of superheated steam, and afterwards revived by being 

 heated in a current of air. A company has lately been formed in 

 New York to apply this process to the production of a brilliant 

 house light. A compound Argand burner is used, having a double 

 row of apertures — the inner row is supplied with oxygen, the other 

 with coal gas or other combustible. The applications of pure 

 oxygen, if it could be procured cheaply, would be very numerous, 

 and few discoveries would more amply reward the inventor. Among 

 other uses, it might be applied to the production of ozone, free 

 from nitric acid by the action of the electrical discharge, and to 

 the introduction of that singular body in an efficient form into the 

 arts as a bleaching and oxidising agent. Tessier de Mothay has 

 also proposed to prepare hydrogen gas on the large scale by heat- 

 ing hydrate of lime with anthracite. We learn from the history 

 of metallurgy that the valuable alloy which copper forms with zinc 

 was known and applied long before zinc itself was discovered. 

 Nearly the same remark may be made at present with regard to 

 manganese and its alloys. The metal is difficult to obtain, and 

 has not in the pure state been applied to any useful purpose ; but 

 its alloys with copper and other metals have been prepared, and 

 some of them are likely to be of great value. The alloy with 

 zinc and copper is used as a substitute for German silver, and 

 possesses some advantages over it. Not less important is the alloy 

 of iron and manganese prepared according to the process of Hen- 

 derson, by reducing in a Siemens' furnace a mixture of carbonate 

 of manganese and oxide of iron. It contains from 20 to 80 per 

 cent, of manganese, and will doubtless replace to a large extent 

 the spiegeleism now used in the manufacture of Bessemer steel. 

 The classical researches of Roscoe have made us acquainted for 

 the first time with metallic vanadium. Berzelius obtained brilliant 

 scales which he supposed to be the metal, by heating oxychloride 

 in ammonia, but they have proved to be a nitride. Roscoe prepared 

 the metal by reducing its chloride in a current of hydrogen, as a 

 light gray powder, with a metallic lustre under the microscope. It 

 has a remarkable affinity both for nitrogen and silicon. Like phos- 



