Some experiments on the changes which take place in the fixed principles of the egg during incubation.

  • Prout, William, 1785-1850.
Date:
1822
Catalogue details

Licence: Public Domain Mark

Credit: Some experiments on the changes which take place in the fixed principles of the egg during incubation. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

    4/26 (page 2)
    Preliminary experiments on the egg in its• recent and unaltered state. The specific gravity of new laid eggs has been found to vary from 1.080 to 1.090. When kept for some time, eggs, as is well known, rapidly lose weight, and become so spe- cifically light as to swim in water. This diminution of spe- cific gravity, however, is only apparent, and depends on the substitution of air for a portion of the water of the egg which escapes ; for it is obvious, that the specific gravity of the con- stituent principles of the egg must be rather increased than diminished by the escape of water. The following table shows the gradual loss of weight of an egg during a period of two years. The original weight on the 19th May, 1820, the day it was laid, was 907.5 grains. Grains. Loss per day. Grains. Loss per day. 19 May, 1820. 20 . . . 24 . . . 31 . . . 8 June . . 17 . . . 27 . . . 19 July . . 7 August . 26 . . . 30 September 907-5 9o6-5 901-3 894.2 886.6 879 3 870.7 848.5 829.6 810.8 778-S 1.00 I.30 1.01 ■95 .81 .86 1.01 -99 •99 .92 5 May, 1821. 6 . . . 5 December 7 • • . 21 March, 1822. 25 April 26 . . . 17 May . . 18 . . . 19 . . . Total Loss 648.7 647.8 488.2 486.6 4135 384.6 3837 365-2 364-3 3632 •59 .90 •75 .80 .70 .82 .90 .84 .90 1.10 544-3 •744 Mean Hence we learn, that a moderately sized egg loses on an average about .75 grain in twenty-four hours, and that