The hand : its mechanism and vital endowments as evincing design and illustrating the power, wisdom and goodness of God / Sir Charles Bell ; preceded by an account of the author's discoveries in the nervous system by Alexander Shaw.

  • Charles Bell
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: The hand : its mechanism and vital endowments as evincing design and illustrating the power, wisdom and goodness of God / Sir Charles Bell ; preceded by an account of the author's discoveries in the nervous system by Alexander Shaw. 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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    ably the ulna projects at the olecranon or elbow, while the radius is still free for rotating : but above all, we cannot fail to observe in the development of one grand metacarpal bone and its corre- sponding phalanges, to the last of which a strong claw is attached, a most efficient instrument for scratching and turning aside aa ant-hill. The whole, therefore, is an example of the relation of the particular parts of the extremity to one another; and were it our business, it would be easy to show that as there is a correspond- ence among the bones of the arm, so is there a more universal relation between those of the whole skeleton. As the structure of the bones of the arm declares the extremity to be adapted for digging into ant-hills, so we shall not be disappointed in our 'ex]3ectation of finding that the animal has a x^rojecting muzzle unarmed with teeth, and a long tongue provided with a glutin- ous secretion, to lick up the emmets disturbed by its scratch- ing. In the skeleton of the Cape-mole, we may see, in the projec- tion of the acromion scapulae, and a remarkable process in the middle of the humerus, a provision for the rotation of the arm; which implies burrowing. But the apparatus is by no means so perfect as in the common mole; so that we may infer that the Cape-mole digs in a softer soil, whilst the possession of gnawing teeth indicates that it subsists on roots. In Birds, there is altogether a new condition of the osseous system, as there is a new element to contend with. The very peculiar form and structure of their skeleton may be thus accounted for. First, it is necessary that birds, as they are buoyed in the air, should be specifically light; secondly, the capacity of their chest must be extended, and the motions of their ribs limited, so that the muscles of the wdngs may have sufficient space and firmness for their attachment. Both these objects are attained by a modification of the apparatus for breathing. The lungs are highly vascular and spongy, but they are not capable of being distended with air; the air is drawn through their substance, passing, by means of numerous orifices, into cells under their skin, and even filling the interior of tlieir bones; so that whilst the great ofiice of decarbonisation of the blood is securely performed, advantage is taken to let the air, warmed and rarefied by the high temperature of their bodies, into all their cavities.
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