y,<^^^hemkal ^cience^X! 417 



cible at the same time covered with its lid. Throw the whole on a 

 .covered filter, and to the liquid whicli passes through add sulphuric 

 acid, or a soluble sulphate; a white powder will precipitate if either 

 baryta, or strontia be present ; but if not, the liquid wiJl retain its 

 transparency. Mixtures of 99.75 parts nitrate of lime, with 0.25 

 part* of either nitrate of baryta or strontia, being thus examined, 

 ffave the precipitates so that a 400th part of these two earths \y^th 

 lime can in this way be detected. — Phil. Mag., N. S., vii. 404. .^ 

 -ni(] ji;i ■ 



ti rilOa Mag?ie$ium. Metal of Magnesia. — M, Bussy has stated at the 

 Academy of Sciences that he has been able to eliminate the base of 

 magnesia by a process similar to that practised by M. Wohler, and 



'iie submitted a specimen for examination. 



h Magnesium has a brilliant silvery white appearance ; is perfectly 

 malleable and ductile ; is fusible at a moderate temperature; like 

 zinc, is volatile at a temperature somewhat higher, and may be 

 condensed again into small globules. It does not decompose water 



•at common temperatures, but is oxidized in the air at high tempe- 

 ratures when in small masses, and gradually forms magnesia. Its 

 filings burn with brilliancy, emitting sparks like iron in oxygen. 

 It is imagined that this metal may be useful, and M. Bussy is en- 

 gaged in searching for a cheap and easy mode of reducing it. 



11. New Metal Thorium^ and new Earth Thorina. — Berzelius has 

 published an account of the discovery of a new metal, which, when 

 oxidized, forms a new earth, and has given the names above to these 

 substances. 



Professor Esmark discovered a mineral which, from its great 

 weight, he thought might be tantalite. It was black, had the ex- 

 ternal appearance of gadolinite from Ytterby; was frangible and 

 not hard. Its specific gravity was 4.63. When heated, it lost its 

 black colour, and evolved water and a little hydrofluoric acid. The 

 mineral appears to exist in very small quantities. None has been 

 jfiwind since the first discovery. 



.lii'The new metallic oxide present in it agrees so nearly with the 

 ; description given of the subphosphate of Ittria, when mistaken by 

 l(Berzelius for a new earth, and called Thorina^ that he has given 

 fibis name to it, and called the metal obtainable from it Thorium; 

 the mineral has been called Thorite. On analyzing the mineral, 

 numerous substances were found in it; the following are their 

 -names, with the quantities of some of them for 100 parts of the 

 If^rite: thorina, 57.91; silica, 18.98; oxide of iron, 3.4 ; Hme, 

 h8.-^6; oxide of manganese, 2.39; oxide of uranium, 1.61; oxide 

 -«tjlead, i 8 ; magnesia, 0.36 ; oxide of tin, potassa, soda, alumina, 

 , boater, 9.5 ; undissolved powder, 1 . 7 : loss, 0.49, 

 yd Thorium,-r-T^h& metal cannot be obtained by the action of potas- 

 t(8ium on th^, t^jde^ but may by the action of potassium upon the 



