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HYPOCHLORITE OE ALUMINA. 
Orioli recommends hypochlorite of alumina to be used 
as a bleaching and disinfecting agent, instead of the hypo¬ 
chlorites of lime and soda. It destroys more promptly, he 
says, organic colouring matter and gaseous matters of a me¬ 
phitic nature. 
ESTIMATION OE NITRIC ACID IN ROUGH SALTPETRE. 
According to Muller this estimation may be made by 
transforming the nitrate of potash into chloride of potassium 
by means of hot hydrochloric acid, the heat being continued 
until the vapour which is evolved no longer affects ozone 
paper. The chloride is weighed after calcination : it must 
be perfectly neutral. 
SEPARATION OE UREA EROM URINE. 
A solution of ammoniacal nitrate of copper, M. de Luna 
has noticed, completely decolorises urine, giving a precipitate 
which contains all the albuminoid and colouring matters of 
that fluid. The perfectly colourless filtered liquid serves 
excellently for the preparation of urea. 
A EOURTH ALKALI-METAL. 
MM. Bunsen and Kirchhoff announce (. Annal.der TJiysiJc 
und Chemie ) that they have discovered a new alkali-metal, 
the fourth member of the group of potassium, sodium, and 
lithium. At present they have only found it in very small 
quantities in the mineral water of Kreuznach, in the saline 
water of Dureckeim, and in one of the sources of the Bade— 
the Umgemach. 
The chloride of the new metal differs from those of sodium 
and lithium by the yellow precipitate which it produces in 
the presence of bichloride of platinum. It is distinguished 
from potassium by its nitrate being soluble in alcohol. In¬ 
troduced into a flame, and examined with a prism, the 
