Q. Why do those that drink and laugh much shed most tears? A. Because that while they drink and laugh without measure, the air which is drawn in doth not pass out through the wind-pipe, and so with force is directed and sent to the eyes, and by their pores passing out, doth expel the humours of the eyes; which humour being so expelled brings tears.
Q. Why do such as weep much, urine but little? A. Because the radical humidity of a tear and of urine are of one and the same nature; and therefore, where weeping doth increase, urine diminishes. And that they are of one nature is plain to the taste, because they are both salt.
Q. Why do some that have clear eyes see nothing? A. By reason of the oppilation and naughtiness of the sinews with which we see; for the temples being destroyed, the strength of the light cannot be carried from the brain to the eye.
Q. Why is the eye clear and smooth like glass? A. 1. Because the things which may be seen are better beaten back from a smooth thing than otherwise, that thereby the sight should strengthen. 2. Because the eye is moist above all parts of the body, and of a waterish nature; and as the water is clear and smooth, so likewise is the eye.
Q. Why do men and beasts who have their eyes deep in their head see best far off? A. Because the force and power by which we see is not dispersed in them, and doth go directly to the thing which is seen. Thus, when a man doth stand in a deep ditch or well, he doth see in the day-time the stars of the firmament; because then the power of the sight and of the beams are not scattered.
Q. Wherefore do those men who have eyes far out in their head not see far distant? A. Because the beams of the sight which pass from the eye are scattered on every side, and go not directly unto the thing that is seen, and therefore the sight is weakened.
Q. Why are many beasts born blind, as lions’ whelps and dogs’ whelps? A. Because such beasts are not yet of perfect ripeness and maturity, and the course of nutriment doth not work in them. Thus, the swallow, whose eyes, if they were taken out when they are young in their nest, would grow in again. And this is the case in many beasts who are brought forth before their time, as it were dead, as bears’ whelps.
Q. Why do the eyes of a woman that hath her flowers stain new glass? And why doth a basilisk kill a man with his sight? A. 1. When the flowers do run from a woman, then a most venomous air is distilled from them, which doth ascend into the woman’s head; and she having pain in her head, doth wrap it up with a cloth or handkerchief; and, because the eyes are full of insensible holes, which are called pores, there the air seeketh a passage and infects the eyes, which are full of blood. The eyes also appear dropping and full of tears, by reason of the evil vapour that is in them; and these vapours are incorporated and multiplied till they come to the glass before them; and by reason that such a glass is round, clear, and smooth, it doth easily receive that which is unclean. 2. The basilisk is a very venomous and infectious animal, and there pass from his eyes venomous vapours, which are multiplied upon the thing which is seen by him, and even unto the eye of man; the which venomous vapours or humours entering into the body do infect him, and so in the end the man dieth. And this is also the reason why the basilisk, looking upon a shield perfectly well made with fast clammy pitch, or any hard smooth thing, doth kill itself, because the humours are beaten back from the hard smooth thing unto the basilisk, by which beating back he is killed.
Q. Why is the sparkling in cats’ eyes and wolves’ eyes seen in the dark and not in the light? A. Because that the greater light doth darken the lesser; and therefore in a greater light the sparkling cannot be seen; but the greater the darkness, the easier it is seen, and is made more strong and shining.
Q. Why is the sight retreated and refreshed by a green colour? A. Because green doth merely move the sight, and therefore doth comfort it; but this doth not black nor white colours, because these colours do vehemently stir and alter the organ and instrument of the sight, and therefore make the greater violence; and by how much the more violent the thing is which is felt or seen, the more it doth destroy and weaken the sense.