182 - Miscellanies. 
would not have found a residue of calcium, uncombined with the ele- 
ments of the glass, That the spangles obtained by Dr. Hare from 
lime, were calcium, was ascertained by their solution in aqua regia, and 
the successive subsequent addition of ammonia and oxalic acid; the 
resulting precipitate being ignited, then redissolved and again precip- 
- itated as at first. No precipitate ensued from the addition of ammo- 
nia prior to that of the oxalic acid. Sulphydric acid produced a slight 
discoloration, but gave no precipitate. That the substances, resulting 
from the ignition of the carbonate with sugar, and washing with ace- 
tic acid, contained calcium in the metallic state, combined with carbon, 
was evident from their being insoluble in acetic or chlorohydric acid ; 
from the deposition 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 excel- 
lent rat of the voltaic fluid. By the ignition of the carbonates 
of a and strontia severally with sugar, Dr. Hare had attained 
ialocone resulis to those above mentioned in the case of the similar 
ignition of carbonate 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 es 
mass was filled with minute metallic globules, which yielded only par- 3 
tially to chlorohydric acid, and which, when dissolved 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 | ize as soon as exposed to the air. He had, however. 
through the kindness of Mr. Booth, a pupil of Wohbler, procured @ 
specimen of magnesium evolved by that celebrated chemist. This 
specimen yielded, under the burnisher, spangles ofa 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 substan- 
ces, as has been lately seen in the case of the reaction of iron with ni- 
tric 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. 
il 5, 1839.—The Committee to whom was referred a paper, €2” 
titled «Contributions to the Geology of the Tertiary Formations of 
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