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tion of carbon, and giving a precipitate of oxalate of lime on being 

 subjected to aqua regia, ammonia, and oxalic acid ; from their metallic 

 brilliancy, when burnished, and from their being excellent conductors 

 of the voltaic fluid. By the ignition of the carbonates of baryta and 

 strontia severally with sugar, Dr. Hare had attained analogous results 

 to those abovementioned in the case of the similar ignition of car- 

 bonate of lime. 



The extreme avidity of calcium for iron was quite striking ; since, 

 when a crucible was inclosed in a clean iron case without a cover, 

 the mass, swelling up so as to reach the iron, became slightly imbued 

 with it. By intensely igniting the carburet of calcium, obtained from 

 the carbonate and sugar, with an equal weight of dry tanno-gallate 

 of iron, the whole of the aggregate became so magnetic that every 

 particle was transferred from one vessel to another by means of a 

 magnet. The mass was filled with minute metallic globules, which 

 yielded only partially to chlorohydric acid, and which, when dis- 

 solved in aqua regia, gave, after adding ammonia and filtration, a 

 precipitate with oxalic acid. 



Dr. Hare was aware that it did not seem consistent that spangles 

 of calcium, burnished upon porcelain, should retain their lustre; 

 as, under other circumstances, and especially when amalgamated, 

 that metal was found to oxidize as soon as exposed to the air. He 

 had, however, through the kindness of Mr. Booth, a pupil of Wohler, 

 procured a specimen of magnesium evolved by that celebrated chemist. 

 This specimen yielded, under the burnisher, spangles of a lustre 

 as enduring as that observed by Dr. Hare in the case of- calcium. 

 It should be recollected that slight causes may affect the oxidability 

 of substances, as has been lately seen in the case of the reaction of 

 iron with nitric acid; and it is well known that silicon, boron, and 

 some other substances have two distinct states, in one of which 

 there is a greater susceptibility of combination with other bodies than 

 in the other. 



