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To this we may add the aptitude of this Figure to the Motion of the Eye, for it is necessary for the Eye to move this way, and that way, in order to adjust it self to the Objects it would view; so by this Figure it is well prepared for such Motions, so that it can with great Facility and Dexterity direct: it self as occasion requires.

And as the Figure, so no less commodious is,

2. The Situation of the Eye, namely in the Head (d\ the most erect, eminent Part of the Body, near the most sensible, vital Part, the Brain. By its Eminence in the Body, it is prepar'd to take in the more (e) Objects. And by its Situation in the Head, besides it Proximity to the Brain, it is in the most convenient Place for Defence and Security. In the Hands, it might indeed (in Man) be render'd more eminent than the Head, and be turned about here and there at pleasure. But then it would be exposed to many Injuries in that active Part, and the Hands (/) render'd a less active and useful Part. And the like may be said to its Sight, in any other Part of the Body, but where it is. But in the Head, both of Man, and other Animals, it is placed in a Part that seems to be contrived, and made chiefly for the Action of the principal Senses.

Another Thing observable in the Sight of the Eye, is the Manner of its Situation in the Head, in

(d) Blemmyis traduntur capita abejfe, Ore Ct" Oculis peflori affixis. Plin. Nat. Hist. 1. 5. c. 8. Occidcntcmveishs quojdata jine cervice Oculos inhumerh habentes. Ib. 1. 7. c. 2. From these, and other such like Fables, in this last cited Chapter of Pliny, no doubt our famous Romancer Sir J. MandeviU, had his Romantick Stories related in his Travels.

(e) See Book V. Chap. z. Note («.)

(/) Galen deserves to be here consulted, who in his Book De Ufa Partium, from many Considerations of the Hand, such as what is here mentioned, as also its Stiucture, Site and Use, largely proves and reflects upon the Wisdom and Providence of the Contriver und Maker of that Part.

the the Fore-part, or Side-part thereof, according to the particular Occasions of particular Animals. In Man, and some other Creatures, it is placed to look directly forward chiefly j but withal it is so order'd, as to take in near the Hemisphere before it. In Birds, and some other Creatures, the Eyes are so feared, as to take in near a whole Sphere, that they may the better seek their Food, and escape Dangers. And in some Creatures they are seated, so as to fee best behind them (g), or on each Side, whereby they are enabled to fee their Enemy that pursues them that way, and so make their Escape.

And for the Assistance of the Eyes, and some of the other Senses in their Actions; the Head is generally made to turn here and there, and move as Occasion requires. Which leads me to the

5. Thing to be remarked upon, the Motions of the Eye it self. And this is generally upwards, downwards, backwards, forwards, and every way (&), for the better, more easy, and distinct Reception of the visual Rays.

But where Nature any way deviateth from this Method, either by denying Motion to the Eyes, or the Head (/'), it is a very wonderful Provision she

hath

(g) Thus in Harts and Conies, their Eyes are very protuberant, and placed so much towards the sides of their Head, that their two Eyes take in nearly a whole Sphere: Whereas in Dogs, (that pursue them) the Eyes are set more forward in the Head, to look that way more than backward.

(k) Sed lubricos Oculos fecit [Natura] v mobiles, ut er dicliuarentfiqnid noceret; e? aspeHum, quo velltnt, facile convenetent. Cicer. de Nat. Deor. 1. 2. c. 57.

(») The Eyes of Spiders, (in some four, in some fix, and in some eight) are placed all in the fore-front of their Head, (which is round, and without any Neck) all diaphanous and transparent, like a Locket of Diamonds, &c. neither wonder -why Providence should be so anomalous in this Animal, more than in any other we know of. For, I. Since they wanting a Neck, tanrtet move their Head, it is requisite that DeftSi should be

fupplit4

hath made in the Case. Thus for a Remedy of this Inconvenience, in some Creatures their Eyes are set out at a Distance (k) from the Head, to be circumvolved here and there, or one this, the other that way, at Pleasure. And in Creatures, whose Eyes are without Motion, as in divers Infects} in this Cafe, either they have more than two Eyes, or their Eyes are nearly two protuberant Hemispheres, and each Hemisphere often consisting os a prodigious Number of other little Segments of a Sphere (I). By which Means those Creatures are so far from being deny'd any Benefit, of that noble and most necessary Sense of Sight, that they have probably

supplied by the multiplicity of Eyes. l. Since they wire to live by catching so nimble a Prey as a Fly is, they ought to fee her every way, and to take her per saltum, (as they do) without any Motion of the Head to discover her; Which Motion would have scared away so timorous an Infect, Power's Micros. Observ. pag. 11.

The Eyes of the Cameleon resemble a Lens, or Convex Glass, set in a versatile globular Socket, which she turneth backward, er any way, without moving her Head; and ordinarily the one a contrary, or quite different way from the other. Dr. Goddard in Phil. Tran. N°. 137.

But what is more extraordinary in this Motion [of the Cameleon% Eye] it to fee one of the Eyes move, whilst the other remains immoveable; and the one to turn forward, at the fame time that the other looketh behind; the one to look up to the Sky, when the other is fixed on the Ground. And these Motions to be so extreme, that they do carry the Pupilla under the Crest which makes the Eye-brow, and so far into the Canthi, or Corners of the Eyes, that the Sight can discern whatever is done just behind it, and direclly before, without turning the Head, -which ts faflned to the Shoulders. Mem. for a Nat. Hist ia Anatom. Dissect, at Paris. Diss. of Camel, pag. n.

0) Snails send out their Eyes at a distance, they being contained in their four Horns, like atramtntous spots, fitted t% she end of their Horns, or rather to the ends of those black Filatnentt or oftick Nerves, which are sheathed in her Horns, as Dr. Power wordeth it. obs. 31 pag. 30\ So the ingenious Pr. Lister. Exercit. Anat. Cochl. y Limac.

(I) yj4, I. 8. f. 3. Note {a).

more more of it than other Creatures, answerable ro the Rapidity os their Flight, and brisk Motion j and to their Inquests after Food, Habitation, or Repositories of Generation, or such other Necessity of the Animal.

4. Another admirable Provision in the Eye, is, its Size; in some Animals large, in some little. It would be endless here to enumerate Particulars; as those of Quadrupeds, Birds, Insects, and other terrestrial Animals. And as for Fishes, they will fall under another Part of my Survey.

I shall therefore only take Notice of its Size in one Creature, the Mole (m), As the Habitation of

that

(m) Sevtr'mus is of Aristotle's, Pliny's, and Alb. Magnus's Opinion, that the Mole liath no Sight; G. Seger denies any Humour to be therein, but thinks they may probably fee, because Nature made nothing in vain. But Borrichius faith, their Eyes have appendiculam ner-jeam in cerebrum cunt au, cujus beneficio globuli Hit [the little Eyes] extra pellem facile tolerant exferi, ritrahique pro arbitrio In Hits oculorum glolulis humor aqueus copiose satis natabat; aterorum non nisi tenuc vestigium. Bias. Anat. Anim. c. 35.

lit qnoniam Nattira hoc vitd genus ipfi destinavit, eliamper

qn'arr. exiguos Oculos dedit eo concilio, ut it, pretiesijfnna

lorporis pars, a tern pulvere ne asstigerentur. li insuper pilis tech, &c. Humores illis oculis insunt, cr tunica nigra, uvea, se prodit. Ad hos tramite alia nervus i-enit. Schneider in Bias. ibid.

Some time since I made divers accurate Dissections of the Eyes of Males, with the help of Microscopes, having a doubt whether what we take to be Eyes, were such or no. And upon a strict Scrutiny I plainly could distinguish the Vitreous and Cryjialline Humours, yea, the Ligamcmum Ciliare, and the atramentaceous Mucus. The Pupil I could manifestly discern to be round, and the Cornea copped, or conical: The Eye is at a great distance from the Brain, the Optick Nerve very flender and long, reaching from the Eye through the intermediate Flesh, and so passeth to the Brain, along with the pair of Nerves reaching to the Nose, which are much the largest that are in all the Animal. These Creatures, 1 imagine, have the Faculty of withdrawing their Eyes,

if

that uncouth Animal is wholly subterraneous, its Lodging, its Food, its Exercises, nay, even all its Pastimes and Pleasures, are in those subterraneous Recesses and Passages, which its own Industry hath made for it self} so it is an admirable Provision made in the Size of the Eye of that little Creature, to answer all its Occasions, and at the fame time to prevent Inconveniences. For as a little Light will suffice an Animal living always under Ground; so the smallest Eye will abundantly supply that Occasion. And as a large protuberant Eye, like that of other Animals, would much annoy this Creature in its principal Business, of digging for its Food and Passage} so it is endow'd with a very small one, commodiousty seated in the Head, and well fenced and guarded against the Annoyances of the Earth.

f. Another Thing remarkable in this noble Part of Animals, is, its Numbers} no less than two (») in any Instance, that I know of} and in some Animals more, as I have already hinted (0).

Now this is an admirable Provision} first, for the Convenience of taking in the larger Angle or Space: And in the next Place, the Animal is by this Provision, in some Measure prepar'd for the

if not quite into the Head, (as Snails) yet more or less within the Hair, as they have more or less Occasion to use or guard their Eyes.

Galen faith, Moles have Eyes, the Crystalline and Vitreous Humours, encompassed with Tunicks. Be Us. Part. I. 14. *. 6. So accurate an Anatomist was he for his Time.

(») Pliny tells us of a fort of Heron with but one Eye, but 'twas only by hear-say. Inter Aves Ardeolarum genere, quos Lcitcos vacant, altero oculo carere tradunt. Nat. Hist. 1, 11. c. 37. So the King of the Nigr*. that hath but one Eye, and that in his Forehead, /. 6. c. 30. Which Fables I take notice of more for the Reader's Diversion, than any Truth in them.

0) Supra, Note (/).

, , Misfortune

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