XIX. Sequel to an essay on the constitution of the atmosphere, published in the Philosophical Transactions for 1826; with some account of the sulphurets of lime

Abstract

In an essay of mine on the constitution of the atmosphere, which was printed in the Transactions for 1826, I signified my intention of following it with a sequel of experiments to ascertain if possible which of the two views therein developed was most countenanced by facts. I now proceed to give an account of such investiga­tions relating to this subject as have engaged my attention during a long period of years. It may be needful to premise certain facts which are, I believe, universally ad­mitted as indisputable; namely, that the atmosphere consists principally of two elastic fluids, azote and oxygen, either mixed by some mechanical law, or otherwise com­bined by a chemical principle in proportion nearly as four parts of the former to one of the latter in volume; that the two elastic fluids may be obtained separately in a state of purity; that when thus obtained they may be mixed in all possible propor­tions; and that the aggregate volumes in such cases are just equal to the sum of the two volumes of the ingredients: also, that any body which has a chemical affinity for either of them so as to combine with it in a separate state, will also combine with it in the mixed state.