ſight of olde men is not ſharpe, becauſe their ſkins are riueled. Whereby it appeareth, that the vertue of the ſight is feeble or ſtrong, by goodnes or feeblenes of the lymme. And he ſaith, When the eyen of beaſts haue lyds, and the humor in the blacke of the eye is cleane and temperate, and ſoft mouing, and the ſkin vpon the blacke, tender, ſupple or thinne, then the ſight is ſharpe and may ſée far. But yet he diſcerneth not perfectly farre off betwéene coulours and difference of the body: but yet the ſight of ſuch beaſts is better, than the ſight of them that haue much humour in the eyen, & haue no heling nor eye lyddes. For by continuall opening, the ſpirite Viſibilis is to diminiſh, and the blacke of the eye is lyghtly grieued and hurt, and ſo the ſight is let. But in men helyngs and eye lids cauſe the contrarie. Alſo there it is ſayd, that cauſe of a ſharpe ſight, in ſéeing a farre, is for the place of the eyen: For big and ouerſwellyng eyen, be féeble of ſight, and ſée not ſo well a farre: but déepe eyen ſee perfectlye a farre of. For the mouing thereof is not departed, nor conſumed, but goeth foorth right, and the ſpirite viſible paſſeth ſtraight forth to the things that be ſeene. And ſo if there bée no heling nor couering without the eye, néedes the ſight muſt be féebled, and ſhal not ſée a farre. Hetherto ſpeketh Ariſtotle lib. 12, & 19. And this that is ſaid generally of the properties of the ſight, ſhal ſuffice at this time. For other things ſhall be knowen héerafter, wher we ſhal treate of the propertie of the eye.
¶Of the hearing. Cap. 18.
THe vertue of hearing, hath effect and doing in the lims of the eares.[1] And the hering is properly a vertue yt perceiueth ſownds: & to make perfect hearing, foure things at the leſt be néedful, yt is to wit, the cauſe efficient, a couenable lim, a niene ſpace bringing ordinately ye ſownd to the wit, and the ſoule taking héede thereto. The cauſe efficient is the vertue that is called. Animalis audibilis, of féelyng and hearing. The couenable lim is a griſtle bone ſet in the eare, and is hollow and drye and ſome deale harde, wound & wrapped as a wiſpe or wreath. It is hollow, that it maye containe the ſpirite and aire in the hollowneſſe therof. It is woond & wrapped as a wreath, leaſt the ſpirit of hearing ſhould be aſtonied and hurt by ſodain and ſtrong ſmiting. And therefore by circularitie of the limme, ſownd temperately receiued, beateth not againe the ſpirit of hearing, but maketh it perfect, and is liking therto. Alſo it is harde and drye, that ſo the ſmiting of the aire may bée made better and ſtronger, and the ſownd the more. As in tabers and timbrels that ſownd better in the Northerne winde that is cold and drye, then in the Southerne winde, that is méeke, moyſt & ſoft,[2] as Conſtantinus and Ariſtotle ſay. The ſpace that bringeth is aire rebounding, that goeth into the holes of the eares, and ſmiteth the griſtle bone, that is the firſt inſtrument and lymme of the hearing, and it needeth that the ſoule take heede, For[3] ſo long as it is thoughtful and intendeth to diuers things, it is the leſſe mightie to doe the deed of the vertue of hearing, as we ſée in many, that be beſet all about: for welnigh they heare nothing, while the thought taketh no héed. And therfore nothing is perceiued by hearing. Hearing is made in this manner. Two ſinewes come out of the inner part of the brayne, & be faſtened in the griſtle bone of the eare: by the which ſinewes, the ſpirite Animalis is brought to the foreſaid griſtle bones, to which griſtle bones the vtter aire referring the ſhape & lykeneſſe of ſome ſownde is meanlye ioyned thereto, and ſo the aire that is ſmitten, ſmiteth thoſe griſtle bones, and in them being the ſpirit, by the propertie of the aire, that is therein ſmiting, the ſinewes is chaunged. And ſo the ſpirite taking a lykeneſſe turneth to his Cell fantaſtike, & preſenteth that lykeneſſe to the ſoule, & ſo the hearing is made perfect. Wherfore it appereth, that the hearing is aire: for alway it is multiplied by rebounding. And therefore it is, that kinde ſet ye wit of hearing, in the middle of the rounde head, as Ariſt. ſaith li. 12. For ye hearing, as it were in a manner winding about,
