576 Chronicles of Science. [ Oct., 
They have been carried out on such a scale and with such pre- 
cautions as are without example in chemical investigations. The 
primary object of M. Stas was to ascertain the truth or falsehood 
of Prout’s theory, that the atomic weights of all simple bodies are 
multiples of that of hydrogen ; the result has been to convince the 
author that the theory is without foundation in fact. We append 
a few of the author’s determinations, reserving a fuller notice of his 
experiments for a future occasion. Taking then hydrogen as the 
unit, the atomic weight of oxygen will be 15-960; of chlorine, 
35°368 ; of iodine, 126°533; of potassium, 39°040; of sodium, 
22:980; and of silver, 107-660. 
Schénbein has published another contribution to the knowledge 
of Peroxide of Hydrogen. In this paper he gives an easy method 
of producing a weak solution of the body, which will probably 
answer to make the tests subsequently described. A small quan- 
tity of amalgamated zinc turnings and a little water are shaken 
for a few minutes in a flask or bottle containing either pure oxygen 
or atmospheric air. By this a little oxide of zinc is formed, and the 
water is found to contain a small amount of peroxide of hydrogen. 
The author states that a strip of white filter paper dipped m a 
solution containing only one-half per cent. of the peroxide, and 
then dried in the air at the ordinary temperature, will show all the 
reactions of the peroxide. When touched with a solution of acetate 
of lead it will turn brownish yellow, and when touched with a dilute 
solution of ferrous sulphate with iodide of potassium and starch, it 
will be instantly coloured the deepest blue. Schdnbein further tells 
_ us that although peroxide of hydrogen is volatile, a solution may be 
concentrated by boiling and indeed almost dehydrated by evapora- 
tion over sulphuric acid and under an air-pump. As showing the 
condition of the oxygen in the peroxide, the author mentions that a 
strip of paper dipped in a solution of the latter, and then suspended 
in a bottle of ozonized air soon ceases to exhibit the reactions of the 
peroxide, while the end of the strip left outside the bottle continues 
to show them for hours. 
The fact that oxygen combines with metals in different condi- 
tions receives further support from an experiment described by 
Dr. W. Schmid. This chemist has found that an excess of freshly 
precipitated peroxide of manganese placed in a solution of sulphate 
of copper causes the precipitation of the latter metal in the form of 
peroxide, the manganese passing into solution as sulphate. 
Tn the list of elements in many works on chemistry the name 
of a supposed metal, Norium, is placed, said to have been discovered 
by Svauberg in 1845. The discoverer thought he had proved that 
zirconia was a mixture of two earths. Recent researches by R. 
Hermann haye however shown that sufficient differences exist in 
zirconia of various origins, mainly depending on the presence of 
