Elements of chemistry, in two volumes / by John Murray.

  • Murray, John.
Date:
1828
Catalogue details

Licence: Public Domain Mark

Credit: Elements of chemistry, in two volumes / by John Murray. Source: Wellcome Collection.

    20/768 (page 8)
    ing at the same time oxygen from the acid and hydro- gen from the water, and the evolved nitrogen and hydro- gen uniting in the moment of their disengagement. The discovery of the existence of oxygen, as a consti- tuent principle of the other two alkalis, potash and soda, suggested the conjecture, that it might exist as an element in the composition of ammonia. Sir H. Davy stated se- veral experiments by which this appeared to be proved, and from which he inferred, that the proportion of oxygen in the composition of ammonia cannot be estimated at less than seven or eight parts in the hundred, and may even be larger. But the reverse was established by the expe- riments of other chemists. Dr Henry, submitting ammo- nia to analysis by the action of electricity, found, when the due precautions have been observed to exclude mois- ture, that it is resolved into hydrogen and nitrogen alone, without any trace of oxygen. The analogical inference, that ammonia must contain oxygen, from the fact, that all other bases which neutralize acids contain that element, has even led some to conclude that oxygen must exist either in hydrogen or nitrogen. This supposition, how- ever, has no support from experimental investigation. It may be remarked, however, that some experimental results have been obtained, which seem to indicate that ammonia, like the other alkalis, is a compound of oxy- gen with a metallic base. The supposed indications of this base have been observed, in submitting the alkali to the powerful decomposing agency of galvanic electricity. Ammonia itself is not easily subjected to the action of gal- vanism, but an ingenious form of experiment was employ- ed by Seebeck, that of placing it in the galvanic circuit in contact with quicksilver. A globule of quicksilver was placed in a solid piece of carbonate or muriate of ammo- nia, slightly moistened, in connection with the positive