déede, and ſo the blacke of the eye in the art of ſeeing is comforted by the ioyning of the vertue of ſight, as it fareth in ſhooters, that cloſe that one eie for to ſhoote the more euen. Alſo the ſpirits Vitalis be therefore ioyned together, that by ſuſteining of each other, they may bée the more ſtrong. And therefore alſo they come and méete together in the bounde of touch, that one thing ſéeme not twaine, the which ſhould fall, if eyther eye a ſunder ſawe his owne Image.
Therefore it néedeth, that the vertue of ſight be conteined in one limme, in the which is one well of vertue, that ſpringeth into ye black of the eie, as ſaith the Authour of Perſpectiue, as it fareth in them that ſet theyr fingers vnder the eyen, in which the blacke of one eye is borne downewarde, and the blacke of the other eie vpwarde. And ſo the ſpirite of ſight is departed and dealed, and one thing ſéemeth twaine. And the cauſe is, for the light commeth from the one eie vpward, and from that other downwarde. And ſo the beame of light yt commeth from either eie, touching the vttermoſt part of the thing that is ſéene, ſetteth not the ſpace, for the aire is betwéene, and ſo he ſéeth as it were two bodies, and yet there is but one. Neuertheleſſe euery ſquint looker ſéeth not ſo, though his eies be vneuen. For ſtéepely the beame paſſeth by a right line to the vttermoſt partes of the thing that is ſéene, as it is ſaid afore in ye third booke, in the Chapter of the ſight. A well diſpoſed eye is conſidered touching the perperfect compoſition of his parts, as it is ſaid afore. Alſo touching the ſcituation: for it challengeth the higheſt place, for the dignitie of his ſubtiltie, & namely for the néerenes it hath with the ſoule, as ſayth Iſidore and Ariſtotle alſo. And touching due proportion of quantitie. For the eie ought not be ſtrained too far out, neither lifted vp too high. For that betokneth diſturbāce of diſcretiō: neither to déep in. For ȳe betokeneth default of matters & of vertue. Then ȳe mene is worthy to be praiſed: but li. 19 Ariſtotle ſaith that a déep ſight ſéeth a far.
For it is moued & lightned ere it come out of ȳe lim, and the light is not departed neither deled: but the beame of ye ſight paſſeth forth right to the things that are ſéene, as it is ſhewed before of the ſight. Alſo it is conſidered by diuers mouings: for it ought to moue meanly: For if ye eie be to much mouing, it betokeneth exceſſe of heate, & betokeneth alſo vnſtedfaſtnes of thought and mutableneſſe of affection. If it moue too ſlowly, it betokeneth the contrary diſpoſition, that is exceſſe of colde and obſtinatneſſe of thought and of will. Then meane mouing is to be praiſed: for it ſignifieth eaſie perceiuing of the minde, and in things perceiued, due faſtning. Therfore Ariſtotle ſaith, li. 12. that the cloſing of the eye muſt be meanely ſwifte, for if it be of great opening and of little cloſing, it betokeneth ſhamefaſtneſſe and folly, as he ſaith li. 1. But if the opening be too ſlowly, it betokeneth default of vertue & compaction of matter in the ſinewes: For it is not obedient ſo ye working of the ſpirit,* as it fareth in them yt haue Lethargia, Forgetfulneſſe, [1]this impediment cōmeth through colde rume, if not of ſome ouer moiſtered impatience, & doth lie in the hinder part of the head or braine pan. Alſo the eies be conſidered properly touching the perfection of their working: For if the eie apprehendeth well and lightly, without againe ſmiting, & déemeth of that he ſéeth, it betokeneth good diſpoſition, as it fareth in the eien of Egles, that ſpéedely behold and ſée the Sun in roundnes. The working of the eie is déemed & conſidered by ſharp & dim. For he that hath a ſubtile ſight, ſéeth well a far off & néere, becauſe the ſight is much, it ſéeth a farre: for it is ſubtill, it hath a full diſcerning of things that be ſéene. For an eie of litle ſight, as Ariſtotle ſaith. li. 19. ſhall not ſée well a farre, for the thicke ſpirit ſéeth much a farre, becauſe of his bigneſſe: but not perfectly becauſe it is thicke. A little ſpirit & ſubtil, ſéeth nigh & perfectly, & not a far, for the ſcarcitie of ye ſpirit of ſight. For when he ſéeth perfectly, yt is by reaſon of the ſubtilty therof. Little ſight & thicke ſeeth not a far, & that is for ſcarcitie therof, nor ſeeth, not perfectly, for ye thicknes therof. For the thicker & the more troubled
- ↑ Addition
