An introduction to medical literature, including a system of practical nosology : intended as a guide to students, and an assistant to practitioners / by Thomas Young.

  • Thomas Young
Date:
1813
Catalogue details

Licence: Public Domain Mark

Credit: An introduction to medical literature, including a system of practical nosology : intended as a guide to students, and an assistant to practitioners / by Thomas Young. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    The tears liave been examined by Fourcroy and Vauquelin: they resemble the humours of the eye; except that, instead of albumen, they hold in solution a particular substance, which is not coagulated by boiling, nor by acids, but which, by slow eva- poration in the open air, is converted into an insoluble mucus, like that of the nostrils. Hence it seems to follow, that the nasal mucus also must be fluid when it is first secreted, and gradually acquire its consistency by exposure to the air in respiration; so that it must be essentially different from the mucus of parts not exposed to the air; [which is also distinguished by not recover- ing its viscidity when dried and again moistened. Afh, III. 8.] 12. Ear. The cerumen has been examined by Vauquelin. It is more or less dry, and consists of a peculiar fatty substance, forming a sort of emulsion with albuminous matter. 13. Skin. The skin, by long boiling, may be changed into gela- tin or glue, which is the better and more adhesive as the skin is more difficultly dissolved. The quality of leather may differ both according to the kind of skin, and to the vegetable substances employedj in tannin. For the preparatory operation of steep- ing the leather, weak alkalis are better than water, and acids, especially vegetable acids, better than alkalis : and a very small quantity of acid may still have a very decided effect. The most important point is, that the process should be conducted slowly and in weak infusions; when it is too much hastened, the external parts of the leather are overloaded with tannin, impede its admission into the internal parts, and afford a hard, brittle, and thin leather. The rete mucosum of Malpighi has not been examined ; it has only been observed that its dark colour in Negroes is bleached for some days by the oxymurialic acid. The epidermis is not solubl'^ by long boiling in water, but is dissolved by caustic al- kalis and by acids, and in most of its chemical relations re- sembles the hair and the nails. Tiie sebaceous matter of the skin