The anatomy of humane bodies epitomized wherein all parts of man's body, with their actions and uses, are succinctly described, according to the newest doctrine of the most accurate and learned modern anatomists / by a Fellow of the College of Physicians, London.

CHAP. XV.

Of the Muscles of the Breast.

HAving done with the Muscles that belong to the Head, the highest Venter, we come now to those of the middle or Thorax, which assist re∣spiration. Of these some dilate the Breast in in∣spiration,* 1.1 some contract it in expiration. Of the Dilaters the first is called par Subclavium. This [ 1] ariseth fleshy from the inner part of the clavicula, and passing obliquely is inserted into the first Rib, [ 2] near to the Sternum. The second is serratum ma∣jus. This doth arise from the inside of the Shoul∣der-blade, and the two upper Ribs, and is insert∣ed into the lower five true Ribs, and two upper short Ribs, before they end into cartilages. It is called serratum or Saw-like, because its unequal extremities being intermixed with the like unequal beginnings of the obliquely descending Muscle of the Abdomen, imitate the Teeth of a Saw. The [ 3] third is serratum posticum superius. This lying under the rhomboides, springeth membranous from the spines of the three lower vertebrae of the Neck,

and of the first vertebra of the Back, and is inserted into the three of four upper Ribs. The fourth is [ 4] serratum posticum inferius. This ariseth from the spines of the three lowest vertebrae of the Back, and of the first of the Loyns, and is inserted into three or four of the lowest (short) Ribs. Fifthly, The [ 5] eleven external intercostals, which perform the of∣fice but of one Muscle. These spring from the lower part of the upper Rib, and are inserted in∣to the upper part of the lower Rib obliquely.

There is another Muscle besides these, that as∣sists the widening of the Breast, namely the Dia∣phragm: but of it we spoke at large in Book 2. chap. 3. where the Reader may find its Descrip∣tion and Use.

These that follow contract the Breast.* 1.2 First, the par triangulare. This arising from the middle Line of the sternum, is inserted into the bony ends [ 1] of the third, fourth, fifth and sixth true Ribs (where they are joined to the Cartilages.) The second is sacrolumbum. This arises from the os sa∣crum, [ 2] and the Processes of the vertebrae of the Loins; and ascending up to the Ribs, is implanted into each of them in their lower side, about three Fingers breadth from the spine, by a particular Tendon. (Diemerbroeck describes another pair op∣posite to this (which he calls cervicale descendens) springing from the third, fourth, fifth, sixth and seventh vertebrae of the Neck, and is inserted into the upper side of each Rib as the sacrolumbum is into the lower. And says, that this pair by pul∣ling the Ribs upwards in inspiration widens the Breast, as the other by drawing them down in expiration straitens it.) Thirdly, The eleven in∣ternal [ 3] intercostals, which are as one Muscle. These

pass obliquely from the lower to the upper Rib. Their Fibres run opposite to those of the external, representing a St. Andrew's Cross, or the Let∣ter X.

These Muscles are much assisted in their action, secondarily, by the Muscles of the Abdomen, sca∣pulae and Arms.

Notes

• * 1.1

  The dila∣ters.
• * 1.2

  The con∣tracters.