Note what service the rounded prominences a b c render; and also all the other shapes of the bones

51 Commence the anatomy at the head and finish it at the soles of the feet. 2 Put in all the passages which the veins make in the flesh and their ramifications between the flesh and the skin. In this way you will locate all the veins which come out between the flesh and skin. 3 Which are the muscles which relax or contract in the movement of any limb in any movement? 4 a shows the way a mouthful of food completes the closure of the epiglottis, b, over the mouth [of the larynx] by which wind enters the lungs. 5 Rule to see how the sound of the voice is generated at the head of the trachea. This will be understood by separating from a man the trachea with the lung; which lung filled with air and then suddenly pressed will immediately enable one to see how the fistula of this trachea generates the voice. And this will be seen and heard well with the neck of a swan or a goose which is often made to sing after it is dead. 6 The two ventricles are those which make the voice sound, and when they are full of humour then the voice is raucous. 7 Break the jaw from the side in order that you see the uvula in its position, what use it is, and how close it is to the mouth of the trachea. 8 One cannot swallow and breathe or give voice at the same time. Nor can one breathe through the nose and mouth at the same time; and this is proved by trying to blow a whistle or flute, one with the nose and one with the mouth at the same time. 9 Why does the voice become high-pitched in old men? The voice becomes high-pitched in old men because all the passages of the trachea are narrowed in the way that other entrails are. 10 Write on what sound is, and what din is, uproar, noise, etc. 11 If you draw in air through the nose and send it out through the mouth you will hear the sound made by the partition [palate] that is the membrane in… 12 Air enters and goes out through the mouth [of the larynx] d, and when food passes over the bridge d n [epiglottis] some particle could fall through the mouth d and pass through c [the rima glottides] which would be fatal. But Nature has arranged the saccules a b [the two ventricles] which receive such a particle and proceed to keep it until with coughing the wind issues with impetus from the lungs by way of c, eddies, and drives the droplets squeezed out by the walls of the saccules a b by way of d; and so this harmful matter is thrown out of its position. 13 The uvula is the gutter whence falls the humour which descends from above and falls by way of the oesophagus into the stomach. It has no occasion to go by way of the trachea to descend into the spiritual parts [i.e. the chest]. 14 Write on the cause of the voice without sound, as do those who speak into the ear of someone else [i.e. whisper]. 15 When one swallows or gulps down a mouthful one cannot breathe. 16 You will demonstrate which muscles push the tongue out of the mouth, how much, and in what way. 17 Note in what part the nerves or cords a b c d arise from the basilar bone [of the skull] and from what ventricle and attach the whole together. And exercise the greatest diligence in demonstrating this movement of swallowing; and also of the high and low voice. 18 you will first make each articulation of the instruments which move, and define them separately, and then put them together bit by bit so that with clear knowledge the whole can be composed. 19 These glands [the thyroid] are made to fill in where the muscles are absent; and they hold the trachea away from the bone of the ‘forcula’ [clavicle]. 20 Draw this trachea and oesophagus cut down through the middle in order to be able to demonstrate the shape of their cavities. Furthermore demonstrate how the bridle [frenum] of the tongue is situated in the tongue. 21 Write on the causes of high- and lowpitched voices.