Vaccination, its natural history and pathology.

  • Copeman, S. Monckton (Sydney Monckton), 1862-
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: Vaccination, its natural history and pathology. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    could then be removed. When this was done, and the material employed for an experimental vaccination, a local result was still obtained, thus showing that the active principle was contained not in these leucocytes, but either in the granules or in the fluid portion of the lymph. In order to settle this point, Chauveau devised a method of diffusion by which he was eventually able to separate the granules from the fluid portion of the lymph. The amount of vaccine lymph at his dis- posal being necessarily exceedingly small, the ordinary means for obtaining diffusion were not applicable. Chauveau attained the desired object, however, by carefully floating a layer of distilled water on to the surface of a drop of lymph contained in a tiny glass vessel of cylindrical shape. If this manipula- tion is dexterously performed, the two liquids do not mix with each other excepting in the immediate neigh- bourhood of the point of junction of the two layers. But after a time the soluble constituents of the vaccine lymph pass upwards into the water, so that if, after twenty-four hours or so, a portion of the upper layer be carefully removed by means of a capillary tube, and examined under the microscope, it is found to be free from granules. And further, Chauveau was enabled to demonstrate the fact that while this upper layer of fluid, which could be shown to contain albumen, and so afforded evidence of diffusion having taken place, gave negative results only on inoculation, the lower layer, on the contrary, which contained the granules in