The text describes various muscles, their origins, insertions, and functions in the human body. The Seratus Major, Rectus, and Triangularis muscles are specifically mentioned, detailing how they attach to the ribs, sternum, and pubic bone. Illustrations referenced in the text provide visual aid for understanding these anatomical descriptions.
Muscles and Their Function
The lumbar muscles originate from the loins, spreading upwards, with their fleshy part implanted in all the false ribs; the Seratus Major (36) adhering saw-like, and its other part with a sinewy surface, implants itself in the White line. This middle line runs over the belly, from the pubic bone (36) and ends close to the sternum or thoracic breastbone. (13) See this Obliquus Externus in illustration A. B.
38. Rectus is the right abdominal muscle, having three or four sinewy bands for its strengthening, helping to narrow the trunk, while expelling wind. It follows the Obliquus Externus, and emerges from above the pubic bone (36), adhering mostly to its side, then gradually separating and increasing in the flesh, it implants itself in the cartilage of the thoracic breastbone (13), yet cut through by three or four sinewy bands, to reinforce the muscle surrounding the belly, see illustration A.
39. Triangularis, is a small triangular muscle, attached to the Rectus; extending from the upper part of the pubic bone (36) and inserts itself into the first bands or straps of the Recti; which bands, in life, are not visibly seen outwardly, other than the location discernible by separation in the abdominal muscle Rectus, although our models keep it obscure to demonstrate. See the mentioned Triangularis in illustration A. 39.