'^'^AvyChemistry. 373 



Hydrobromic acid = {^1:27^X0 "en 

 And the spec. grav. of gaseous hydrobromic acid == 2.7311. 



It will be remembered that Dr Thomson's number for iodine is 15.5. 

 and that Balard's two experiments gave for that of bromine 932.6, and 

 942.9 ; while Liebeg's later experiments gave for that of bromine 942.9. 



8. Analysts of a Meteoric Stone. — This stone fell in Macedonia, and was 

 analyzed by Berzelius at the request of Mr Schener of Vienna, for a work 

 on meteoric stones which he is preparing. 



It was of a grey colour, intermixed with round transparent specks; and 

 with points of a dark or brown colour and metallic lustre, showing it to be 

 an aggregate of several different substances. Rubbed to powder, the mag- 

 net separated it into two portions ; and the non-magnetic portion treated 

 with acids left 52^ per cent, of insoluble matter. 

 The magnetic portion consisted of 



Iron, - - . gggg 



Nickel, with a trace of cobalt, - 4.80 



Sulphur, - - - 6.83 



100 



and was a mixture of nickel, iron, and magnetic pyrites, both of which the 



magnet had drawn out together. 



The non-magnetic portion soluble in muriatic acid consisted of 

 Silica, ... 28.70 



Protoxide of iron, - - 29.60 



Magnesia, - - > 40. 



Potash, - - - 8 



Soda, - - - 9 



having the composition of olivine, with this diflPerence, that the oxygen in 



the bases is to that in the s,ilica, as 3 : 2, 

 The insoluble portion consisted of a mixture of the silicates of potash 



and soda, iron, manganese, lime, alumina, magnesia, with one per cent, of 



protoxide of chromium, and .2 per cent, of oxide of nickel. — Transactions 



of the Royal Academy of Sciences of Stockholm. 



III. NATURAL HISTORY. 

 MINERALOGY. 



9. Analysis of Allophane from Firmi in the Aveyron. By M. J. GuiL- 

 LEMiN. — The specific gravity was 1.76 at 19° Reaum. 



Firmi Schneiberg 



Guillemin. Stromeyer. 



Silex, - - - 22.00 21.92 



Alumina, - - 35.00 32.20 



Water, - - 42.00 41.30 



Sulphuric acid, - - 0.75 0.52 



Lime, - - _ traces, 0.73 



Oxide of iron, - - 0.00 3.33 

 Carbonate of copper. 



99.75 100.00 



