_a b c_ are equal to each other and to the foot and to the space between the nipple and the navel _d e_ will be the third part of the whole man. _f g_ is the fourth part of a man and is equal to _g h_ and measures a cubit. [Footnote: See Pl. XIX, No. 1. 1. _mamolino_ (=_bambino_, little child) may mean here the navel.] 348. _a b_ goes 4 times into _a c_ and 9 into _a m_. The greatest thickness of the arm between the elbow and the hand goes 6 times into _a m_ and is equal to _r f_. The greatest thickness of the arm between the shoulder and the elbow goes 4 times into _c m_, and is equal to _h n g_. The smallest thickness of the arm above the elbow _x y_ is not the base of a square, but is equal to half the space _h_ 3 which is found between the inner joint of the arm and the wrist joint. [11]The width of the wrist goes 12 times into the whole arm; that is from the tip of the fingers to the shoulder joint; that is 3 times into the hand and 9 into the arm. The arm when bent is 4 heads. The arm from the shoulder to the elbow in bending increases in length, that is in the length from the shoulder to the elbow, and this increase is equal to the thickness of the arm at the wrist when seen in profile. And the space between the bottom of the chin and the parting of the lips, is equal to the thickness of the 2 middle fingers, and to the width of the mouth and to the space between the roots of the hair on the forehead and the top of the head [Footnote: _Queste cose_. This passage seems to have been written on purpose to rectify the foregoing lines. The error is explained by the accompanying sketch of the bones of the arm.]. All these distances are equal to each other, but they are not equal to the above-mentioned increase in the arm. The arm between the elbow and wrist never increases by being bent or extended. The arm, from the shoulder to the inner joint when extended. When the arm is extended, _p n_ is equal to _n a_. And when it is bent _n a_ diminishes 1/6 of its length and _p n_ does the same. The outer elbow joint increases 1/7 when bent; and thus by being bent it increases to the length of 2 heads. And on the inner side, by bending, it is found that whereas the arm from where it joins the side to the wrist, was 2 heads and a half, in bending it loses the half head and measures only two: one from the [shoulder] joint to the end [by the elbow], and the other to the hand. The arm when folded will measure 2 faces up to the shoulder from the elbow and 2 from the elbow to the insertion of the four fingers on the palm of the hand. The length from the base of the fingers to the elbow never alters in any position of the arm.