The text elaborates on the skeletal and muscular structures of the human body, particularly focusing on how bones like the sternum and shoulder blades are connected. It describes muscles as structures that enable movement by attaching to bones, receiving sustenance from arteries, and being controlled by nerve impulses. The description highlights the muscles’ various shapes and functions, emphasizing their role in voluntary movements and the changes they cause to the body's form.
THE DRAWING.
Bones. These are attached at one end to the sternum, and on the other end, they join, each on its side, to the shoulder blades, which being flat and very broad bones, cover the first ribs from the back. It is to these transverse bones and the joined shoulder blades that the shoulder sockets are attached, where the arm bones are inserted. To these arm bones are attached the elbow bones, which are double; the one on the thumb side is called the radius or ray: the other, which is on the little finger side, is called the ulna or elbow bone: to these two bones, the two hands are attached.
Of Muscles and their Use. Plates 4, 5, & 6.
The entire mechanism that comprises the human body moves through the muscles that make the bones, to which they are attached, advance or retract. These muscles are flesh woven with fibers and membranes: they are of different shapes, but they always swell in the middle, and their extremity or tail ends in tendons with which voluntary movements are made. These muscles are placed next to each other on the bones, receive their sustenance through the arteries, and the animal spirits are sent to them by the nerves; thus, when they swell, they shorten and move the limbs in various ways, making them take different forms, and causing bulges or indentations following the variety of their actions. These bulges and indentations are softened by smooth but thick skin, which covers the body completely, rising in some areas more than others, so that there are places where it is hard to recognize the muscles beneath.
The main muscles that move the bones and