Chemical Notes

    Article metrics


    VARIATIONS IN THE CRITICAL POINT OF CARBON DIOXIDE IN MINERALS, AND DEDUCTIONS FROM THESE AND OTHER FACTS.—Mr.W.N. Hartley has continued his experiments on this subject, and gives in a paper read lately before the Chemical Society further conclusions as to the existence of the expansible fluids in mineral cavities. He concludes it to be carbon dioxide from the spectrum produced by the electric spark in a tube containing such gas as was liberated by the decomposition of the minerals; the turbidity produced by crushing quartz under baryta water (Vogelsang and Geissler, 1869); the rate of expansion of the liquid in sapphire compared with that of carbon dioxide (Sorby and Butler, 1869) and the determinations of the critical point made by himself in 1875–76. To determine the critical point he uses small thermometers made specially for the purpose, one having a range from — 20 to 140° F., the other graduated to register tenths of a degree from 25° to 33° C. The following table shows all the variations noticed in the critical point of carbon dioxide existing in various minerals:—

    Rights and permissions

    Reprints and Permissions

    About this article

    Cite this article

    Chemical Notes . Nature 15, 167 (1876) doi:10.1038/015167a0

    Download citation


    By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.