Experiments and observations to investigate the composition of James's powder / [George Pearson].

  • George Pearson
Date:
[1791]
Catalogue details

Licence: Public Domain Mark

Credit: Experiments and observations to investigate the composition of James's powder / [George Pearson]. Source: Wellcome Collection.

    17/44 (page 15)
    concretions, of the size of black pepper seeds. The products were the same as the former, but the gaz was still more offen- sive, and in smaller quantity; and the carbonaceous matter was more copious. I, in the same way, subjected to experiment 20 grains of a nut-brown light calculus, which I had previously ascertained to contain the matter above described, which was precipitated from caustic soda by acids. The products were of the same kind as the former; but I could find no trace of phosphoric acid in the residue, which I did of lime, and the gaz was less offen- sive. The carbonaceous residue was not, in weight, 3 grains. It will be proper, before I proceed further, to point out some of the more obvious conclusions from the above experi- ments. 1. It appears that at least one half of the matter of the urinary concretions subjected to the above experiments united to caustic soda, and was precipitated from it by acids. (IL a—d.) 2. This precipitate does not indicate acidity to the most de- licate tests; (e, 2.) and, as it is inodorous, tasteless, [e, 1.) scarcely soluble in cold water, (^, 2.) does not unite to the alkali of carbonate of potash, of soda, or of ammoniac, 4.) nor to oxide of mercury, (^,4.) nor to the lime of lime wa- ter, [e, 8.) nor decompound soap, (^, 10.) or prussiate of iron, (e, 13.) and, as its combination with caustic soda resembles soap, more than any double salt known to consist of an acid and alkali, this precipitate does not belong to the genus acids. 3. As this precipitate could not be sublimed, without being decompounded, like animal matter, (^, 15.) and also for the C 2