A compendium of the anatomy of the human body: intended principally for the use of students (Volume 2).

  • Fyfe, Andrew, 1754-1824.
Date:
1810
Catalogue details

Licence: Public Domain Mark

Credit: A compendium of the anatomy of the human body: intended principally for the use of students (Volume 2). Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    APPENDAGES OF THE SKIN. Naii.s. The Nails were formerly regarded as a continuation of tlie Papilla; of the Cutis* but are now more generally considered as a continuation of the Cuticle. They are removed along with it by boiling water, or by maceration. Like the Cuticle also, they are insensible, are re- newable after having been separated, and have no evi- dent Vessels- Thev differ from it, however, in structure, being formed of Plates, and these ofLongitudinal Fibres, which are closely compacted. They begin by a square root, a little before the last Joint of the Fingers and Toes. When separated from the Skin, they are transparent like Horn, but are coloured in the living Body by the Vessels of the Cutis, to which they adhere, and from which they derive their nourishment. They are fixed at their roots to a semilunar fold of the Cutis, and are there covered by a reflection of the Cuticle, which firmly adheres to them. They grow from the roots, and not from the points. The nails strengthen and defend the ends of the Fin- gers and Toes, and thereby serve as Buttresses. In the Fingers they increase the power of apprehen- sion, being useful in laying hold of minute objects. Hairs. The Hairs arise by roots or bulbs, which are situa- ted in the Cellular Substance under the Skin. The Bulbs are of various shapes in different parts of the Body, and have Blood-Vessels dispersed upon them for their nourishment. Each of the Bulbs has tin a Membranes, or Capsules, ining an Oily Fluid between them, which gives colour to the Hair, and for want of which, as on ad- vanced life, or in certain diseases, the hair is supposed to change its colour, and become white. It may be re-