202 ANNUAL OF SCIENTIFIC DISCOVERT. 



since, if the two kinds of oxygen enter into combination, it is 

 probable that the elements with which they combine exist in two 

 allotropic states. The facts which demonstrate that the oxygen 

 elements in the peroxides of manganese and barium are in very 

 different states are very remarkable, and are such as admit of no 

 doubt. Thus the oxygen in the peroxide of barium has a less 

 affinity for hydrogen and chlorine, since, when it is acted on by 

 the latter, hydrochloric acid will be formed, oxygen being given 

 off; while, on the contrary, hydrochloric acid is decomposed by 

 peroxide of manganese, chlorine being evolved. It is worthy of 

 remark that the oxygen given off by the peroxide of barium is in 

 the form of ozone. Again : if peroxide of barium is treated with 

 hydrochloric acid, peroxide of hydrogen will be formed ; but if 

 peroxide of manganese is treated with the same acid, ordinarily 

 water will be formed, and chlorine evolved. Sulphovinic acid, if 

 treated in presence of peroxide of barium, affords either bicarbu- 

 ret of hydrogen or other substances ; but, if in presence of perox- 

 ide of manganese, aldehyde. 



Peroxide of hydrogen may be formed by means of either per- 

 oxide of barium or peroxide of manganese ; but the two perox- 

 ides of hydrogen thus obtained are very different, since each will 

 be decomposed by the peroxide employed in forming the other ; 

 and, what is still more remarkable, they will decompose each 

 other. 



ON THE ORIGIN OF METEORITES. 



In his researches on diffusion, Graham has shown that certain 

 metals, such as iron, platinum, and gold, which occur native in 

 the soft colloid condition, readily absorb or occlude gases. Hence 

 by examination of the gases evolved from a meteorite, for exam- 

 ple, the character of the atmosphere through which the ignited 

 mass has passed may be determined. The well-known Lenarto 

 meteorite is admirably adapted for such an experiment, being 

 very pure and soft. A piece 50 millimetres long, 13 wide, and 10 

 thick, was cut oft* from the mass, cleansed, and placed in a porce- 

 lain tube connected with a Sprengel aspirator. The tube was 

 then heated in an ordinary combustion furnace by ignited char- 

 coal. Gas was freely evolved, which in 2i hours amounted to 

 16.53 cubic centimetres. This gas burned like hydrogen, and 

 when analyzed gave 85.68 hydrogen, 4.46 carbonic oxide, 9.86 

 nitrogen in the 100. As the volume of the iron was 5.78 c.c., it 

 appears to yield 2.85 times its volume of gas, of which 86 per 

 cent, is hydrogen. Now, since hydrogen has been shown by 

 spectrum analysis to be present in the fixed stars, and by Secchi 

 to be a principal element in some of them, we may fairly suppose 

 that the Lenarto meteorite has brought to us the hydrogen of 

 those distant bodies. Moreover, it is found that malleable iron 

 can scarcely be made to occlude more than its own volume of hy- 

 drogen under the ordinary atmospheric pressure. But the meteor- 

 ite gave three times this quantity. Hence Graham infers that it 



