A treatise on the digestion of food / by G. Fordyce, M. D. F. R. S. fellow of the Royal College of Physicians, and reader on the practice of physic, in London.

  • Fordyce, George, 1736-1802.
Date:
1791
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the digestion of food / by G. Fordyce, M. D. F. R. S. fellow of the Royal College of Physicians, and reader on the practice of physic, in London. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

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    I I* ] bach is of different degrees of moifture or drynefs, the appearances are extremely dif- ferent. The manner in which I have been able to get it moil diftind:, was by placing a fmall portion of the interior part upon a fmall circular plate of ivory, with the fur- face outward and in view -3 this fmall plate of ivory was fixed in the centre of a circular plate of glafs, which fitted the ftage of a compound microfcope, and a filver concave mirror was applied at the object end of the microfcope to reflect the light, as ufual in viewing opake bodies. When the furface was moderately moid, there appeared a number of fine thin membranes, crofiing one another fo as to form a number of irre- gular cells; and the furfaces of each of thefe membranes were covered again by finer and fmaller membranes again crofiing one another, fo as to form letfer and fhallower cells, fo as very much to increafe the inte- rior furface 5 and this appearance accords with what is feen by the naked eye, or a glafs of little magnifying power, and very much refembles a piece of pumice frone broken.