Then indicate the pectoral markings in their places relative to the armpits. A line connecting them should run fairly parallel to the collar-bones. Ascertain and mark the position of the centre line of the body between the pectoral markings. Then measure the length of the space to the navel, taking the head and neck as your standard. The three markings, the two pectoral and the navel, make a triangle which varies in its nature according to the character and action of the torso, and is always the key to its movement. Sometimes acute when the body is upright or thrown back, it is more obtuse when the body is seated or bent forward, as in the torso Belvedere. Follow the central abdominal marking to its base, and take care that the curve of the whole central line from the neck to the base of the torso is closely followed.
Draw the inner line of the left arm ; compare the length of the part of that line between the armpit and the highest point of the passage lying between the arm and the body. Compare the length of that background space and draw it in freehand ; and it will leave for you the exact direction and form of the upper arm and the side of the torso, and will clearly indicate the position of the left hip.
Then pass on to the right side, making careful use of the shape of the background lying between the outline of the torso and the raised arm, and refer to the upright line on the background in seeking the exact direction of the outline.
Before going further, indicate all the internal markings.
Note that, the body being contracted on the left side and extended on the right, the lines radiate from the crease and the hip on the left, so that the pectoral marking and the edge of. the fixed ribs on the right are higher than their counterparts on the left, but that the hip on the right is considerably lower than that on the left.