The principles of anatomy and physiology applied to the preservation of health / by Joseph Brown Walker.

  • Walker, Joseph Brown.
Date:
1844
Catalogue details

Licence: Public Domain Mark

Credit: The principles of anatomy and physiology applied to the preservation of health / by Joseph Brown Walker. 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.)

    6/32
    [6] account of its tonic and anti-septic powers. But very of- ten all these will fail, and the only infallible cure is to draw the tooth. We next come to the bones of the body or trunk. The spine or back bone consists of twenty-four small pieces, termed vertebra, from the Latin word vertere to turn, as the body turns on them as on a pivot. Of these, seven are called cervical vertebra, belonging to the neck; twelve dorsal vertibrae, connecting the ribs at the back ; and five lumbar belonging to the loins. The base of the column rests on the bone which connects the hip bones on the back of the pelvis, called tbe sacrum, below which is a small bone, the os coccygis, named from its resem- blance to the cuckoo's bill, which teiminates below what is called the back bone. The vertebra are firmly bound to each other in such a way as to admit of flexion and ex- tension, and a certain degree of rotation, while by their solidity and firm attachment to each other, great strength is secured. Some conception of this strength may be formed, when we consider the enormous loads which some athletic men are able to carry on their shoulders, or raise in their hands, the whole weight of which is necessarily borne by the vertebra of the loins. As the space occu- pied by the abdomen gives large outward dimensions to this region of the body, it is only upon reflection that we perceive that the whole force exerted by the human frame in its most strenuous efforts, centres, ultimately, in the bony column of the spine. While the body of the verte- bra affords support to the superincumbent parts, the.pro- jecting ridge behind, and rugged processes at the sides, combine with it to form a large tube or canal, extending from the top to the bottom of the column, in which the spinal marrow >s contained and protected. Between each of the vertebra a thick compressible cushion of cartilage and ligament is interposed, which serves to unite the bones to each other, to diminish the shock in walking or leaping, and of admitting a greater extent of motion than if the bones were in immediate contact. The ribs are twelve in number on each side, attached by their heads to the spine, and by their T>ther (cartilag-