260 Scientifie Intelligence. 
ful amethystine tint, if it contains any manganese; by exposure to 
the light of the sun the fluid soon becomes colorless, but the color may 
be again renewed by placing the bottle in the dark. 5GL:S. 
10. Separation of Cobalt from Manganese ; (Journ. de Pharm, March, 
1846.)—M. Barreswil has taken advantage of the fact that sulphuretted 
hydrogen will precipitate cobalt froma perfectly neutral solution of all 
its salts, but not the manganese. The object to be arrived at, is to keep 
the solution neutral as the cobalt is precipitated, which is done as fol- 
lows :—An excess of carbonate of baryta is added to the solution con- 
taining the cobalt and manganese, and through it the sulphuretted 
hydrogen is passed. The cobalt is precipitated, the manganese re- 
mains in solution, and the carbonate of baryta keeps the solution neu- 
tral without interfering with the result. The rest of the analysis is 
conducted in the ondietty way. J. Lx Bi 
‘11. Upon the Precipitation of different Oeiparse and Mineral Sub- 
stances by Animal Charcoal ; by M. Werrens, (Rev. Scientifique, Feb., 
1846, p. 251.)—The animal charcoal used was prepared from bones, 
and washed repeatedly with boiling hydrochloric acid in order to dissolve 
the phosphate of lime. Thus prepared it precipitates bitter extracts, 
resins, and astringent substances from solution. 5 parts of colocynth, 
gentian, columbo, and quassia being infused in 600 parts of water, this 
latter was completely deprived of its bitter taste by 16; 10, 5, and 16 
parts of charcoal respectively for the four substances mentioned. 600 
parts of water containing 14 of aloes was rendered tasteless by 21 
rts of charcoal. The sulphates of copper, zinc, chrome, iron, the 
nitrates of mercury, nickel, cobalt, silver and other metallic: salts are — 
to a certain extent precipitated by animal charcoal. Sule Sy 
12. On the Incandescence of Iron, Copper, Brass, &§c., in the Vapor 
of Alcohol; by Prof. Borrerr, (Annalen der Pharm. und Chem., Jan., 
1846.)—Dr. Riensch has lately discovered that the above metals heated 
_ toa certain point, would, under favorable circumstances, glow in the 
vapor of alcohol. Prof. Bottger endeavors to show that this phenom 
enon is not attributable to the metals themselves, but rather to their OX- 
ides, for he says every one who has performed the experiment as a 
scribed by the author, must have found that it requires a long time for 
it to succeed perfectly, and when it is successful it will be found that it 
is owing to the surface of the iron having become oxydized. He farther 
states, that a coil-of wire, which from repeated use has been super 
ficially converted into oxide, will glow in the vapor of aleohol — as 
— pure metallic platinum. —_. JL.S 
iB Astras: Simple Method of proprig Chlorie Acid Pot 
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