The Romance of Modern Chemistry

CHEMISTRY OF THE STARS terrestrial in their origin, and have been projected into space from active volcanoes in long-past ages of the earth’s history; but the opposite opinion is most widely held, namely, that they are genuine samples of celestial matter. An inspection of the fine collection of meteorites in the Natural History Museum at South Kensington will show that many of them consist to a large extent of iron, or rather of an alloy of iron with a small percentage of nickel. Other meteorites contain but little iron, and are more like stones in their composition. Altogether there is considerable similarity in the composition of meteorites which have fallen at different times and in different places, and this uniformity has suggested to some scien- tists that most meteorites, if not all, have come from a common source, and are possibly chips of one heavenly body. No single element has been found in a meteorite which is not obtainable also from terrestrial sources. The ones which occur most commonly in these other-world chips, in addition to iron and nickel, are aluminium, calcium, carbon, magnesium, oxygen, phosphorus, silicon, and sulphur, all in a state of combination. Some, indeed, of the compound minerals occurring in meteorites are new, and it is curious that quartz, the most common of terrestrial minerals, should not be found in meteoric stones. The study of the composition of these celestial visitors is of the greatest interest, but it is not from them that our trustworthy information about the constitution of the sun and stars is derived. This information is obtained in a much more wonderful fashion; it is based, not on any laboratory examination of celestial specimens, but on a 205