Spirit-gravities, with tables / by Thomas Stevenson.

  • Stevenson, Thomas, 1838-1908.
Date:
1880
Catalogue details

Licence: Public Domain Mark

Credit: Spirit-gravities, with tables / by Thomas Stevenson. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    11/94
    referred to as a -well-determined result; but it is not so, and its accuracy appears to be more than doubtful. Tralles having determined to adopt the work of Gilpin, it became necessary to deter- mine how much water is contained in alcohol of the specific gravity -825 (Gilpin’s alcohol). By a series of experiments this was found to be 92-6 per cent, of Tralles’s alcohol by volume, or 89-2 per cent, by weight. The true percentage of absolute alcohol in Gilpin’s alcohol is 89-05 per cent, by weight, or 92-55 per cent, by volume. The table of Tralles, found in many text-books, gives in one column the specific gravities at 60° l-’ahr. (water at 4° C.=l), and in another the percentages of alcohol by volume. The range is from pure water, sp. gr. -9991, to alcohol, sp. gr. •7939. Tralles did not publish the experiments from which he deduced his conclusion that Gilpin’s alcohol contained 89-2 of Tralles’s alcohol; and Gilbert says that the data were not among the papers confided to him. Dividing Tralles’s gravi- ties by -9991, to mako them comparable with Gilpin’s, and assuming that Tralles’s alcohol con- tained 100 x = 99-83 per cent, of absolute alcohol by weight, or 99-93 per cent, by volume, I have compared Tralles’s table with Gilpin’s at the several points at which their specific gravities (reduced for temperature) are comparable; and I find the following results at the points where the specific gravities are practically coinci- dent :—