FOOTNOTES:
[a] Ex sensibus ante cætera Homini Tactus, deinde Gustatus: reliquis superatur à multis. Aquilæ clariùs cernunt: Vultures sagaciùs ordorantur, liquidiùs audiunt Talpæ obrutæ terrâ, tam denso atque surdo naturæ elemento. Plin. Nat. Hist. l. 10. c. 69.
[] Subjacent Oculi, pars corporis pretiosissima, & qui lucis usu vitam distinguant à morte. Plin. Nat. Hist. l. 11. c. 37.
[c] Fœminæ aliquæ Megarenses solis oculis discernere valebant inter Ova quæ ex Gallinâ nigrâ, & quæ ex albâ nata sunt, is what is affirmed (how truly I know not) by Grimald. de Lumin. & Color. Pr. 43. §. 60.
CHAP. II.
Of the Eye.
For our clearer Proceeding in the Consideration of this noble Part[a], and understanding its Oeconomy, I shall consider:
1. The Form of the Eye.
2. Its Situation in the Body.
3. Its Motions.
4. Its Size.
5. Its Number.
6. Its Parts.
7. The Guard and Security Nature hath provided for this so useful a Part.
As this eminent Part hath not been pretermitted by Authors, that have made it their particular Design and Business to speak of the Works of God; so divers of the aforesaid Particulars have been touched upon by them. And therefore I shall take in as little as possible of what they have said, and as near as I can, mention chiefly what they have omitted. And,
1. For the Form of the Eye; which is for the most part Globous, or somewhat of the sphæroidal Form: Which is far the most commodious optical Form, as being fittest to contain the Humours within, and to receive the Images of Objects from without[]. Was it a Cube, or of any multangular Form, some of its Parts would lie too far off[c], and some too nigh those lenticular Humours, which by their Refractions cause Vision. But by Means of the Form before-mentioned, the Humours of the Eye are commodiously laid together, to perform their Office of Refraction; and the Retina, and every other Part of that little darkned Cell, is neatly adapted regularly to receive the Images from without, and to convey them accordingly to the common Sensory in the Brain.
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 its 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[f] 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 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; 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 seated, 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 see best behind them[g], or on each Side, whereby they are enabled to see 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
3. Thing to be remarked upon, the Motions of the Eye it self. And this is generally upwards, downwards, backwards, forwards, and every way[h], 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 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 Insects; in this Case, either they have more than two Eyes, or their Eyes are nearly two protuberant Hemispheres, and each Hemisphere often consisting of a prodigious number of other little Segments of a Sphere[l]. 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 more of it than other Creatures, answerable to the Rapidity of their Flight, and brisk Motion; 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 thole 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 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 same 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, commodiously seated in the Head, and well fenced and guarded against the Annoyances of the Earth.
5. Another Thing remarkable in this noble Part of Animals, is, its Numbers; no less than two[n] in any Instance, that I know of; and in some Animals more, as I have already hinted[o].
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 Misfortune of the Loss of one of these noble, and necessary Organs of its Body.
But then besides all this, there is another Thing considerable in this multiplicate Number of the Eye; and that is, that the Object seen is not multiplied as well as the Organ, and appears but one, though seen with two or more Eyes[p]. A manifest Sign of the infinite Skill of the Contriver of this so noble a Part, and of the exquisite Art he employed in the Formation thereof. But the Design and Skill of the infinite Workman, will best be set forth by
6. Surveying the Parts and Mechanism of this admirable Organ the Eye. And here indeed we cannot but stand amazed, when we view its admirable Fabrick, and consider the prodigious Exactness, and the exquisite Skill employed in every part ministring to this noble and necessary Sense. To pass by its Arteries and Veins, and such other Parts common to the rest of the Body, let us cast our Eye on its Muscles. These we shall find exactly and neatly placed for every Motion of the Eye. Let us view its Tunicks, and these we shall find so admirably seated, so well adapted, and of so firm a Texture, as to fit every Place, to answer every Occasion, and to be Proof against all common Inconveniences and Annoyances. Let us examine its three Humours, and these we shall find all of exquisite Clearness and Transparency, for an easy Admission of the Rays; well placed for the refracting of them, and formed (particularly the Crystalline Humour) by the nicest Laws of Opticks, to collect the wandring Rays into a Point. And to name no more, let us look into its darkned Cell, where those curious Humours lie, and into which the Glories of the Heavens and the Earth are brought, and exquisitely pictured; and this Cell we shall find, without, well prepared by Means of its Texture, Aperture, and Colour, to fence off all the useless or noxious Rays; and within, as well coated with a dark Tegument, that it may not reflect, dissipate, or any way confuse or disturb the beneficial Rays[q].
But to descend to Particulars, although it would be a great Demonstration of the Glory of God, yet would take up too much Time, and hath been in some Measure done by others that have written of God’s Works. Passing over therefore what they have observed, I shall under each principal Part take a transient Notice of some Things they have omitted, or but slightly spoken of.
And my first Remark shall be concerning the Muscles of the Eye, and their Equilibration. Nothing can be more manifestly an act of Contrivance and Design, than the Muscles of the Eye, admirably adapted to move it any, and every way; upwards, downwards, to this side or that, or howsoever we please, or there is occasion for, so as to always keep that Parallelism of the Eye, which is necessary to true Vision. For the Performance of which Service, the Form, the Position, and the due Strength of each Muscle is admirable. And here I might Instance the peculiar and artificial Structure of the Trochlearis, and the Augmentation of its Power by the Trochlea[r]; the Magnitude and Strength of the Attollent Muscle, somewhat exceeding that of its Antagonist; the peculiar Muscle, called the Seventh, or Suspensory Muscle[], given to Brutes, by reason of the prone Posture of their Bodies, and frequent Occasions to hang down their Heads: And I might speak also of the peculiar Origine and Insertion of the lower Oblique Muscle[t], which is very notable, and many other Things relating to these Parts; but it would be tedious to descend too much to those admirable Particulars. And therefore to close up these Remarks, all I shall farther take Notice of, shall be only the exquisite Equilibration of all these Opposite and Antagonist Muscles, affected partly by the Equality of the Strength; which is the Case of the Adducent and Abducent Muscles; partly by their peculiar Origine, or the Addition of the Trochlea, which is the Case of the Oblique Muscles[]: and partly by the natural Posture of the Body, and the Eye, which is the Case of the Attollent and Depriment Muscles. By this so curious and exact a Libration, not only unseemly Contortions, and incommodious Vagations of the Eye are prevented, but also it is able with great Readiness and Exactness to apply it self to every Object.
As to the Tunicks of the Eye, many Things might be taken notice of, the prodigious Fineness of the Arachnoïdes, the acute Sense of the Retina, the delicate Transparency of the Cornea[w], and the firm and strong Texture of that and the Sclerotica too; and each of them, in these and every other respect, in the most accurate manner adapted to the Place in which it is, and the Business it is there to perform. But for a Sample, I shall only take notice of that part of the Uvea which makes the Pupil. It hath been observed by others, particularly by our Honourable Founder[x], That as we are forced to use various Apertures to our Optick Glasses, so Nature hath made a far more compleat Provision in the Eyes of Animals, to shut out too much, and to admit sufficient Light, by the Dilatation and Contraction of the Pupil[y]. But it deserveth our especial Remark, that these Pupils are in divers Animals of divers Forms, according to their peculiar Occasions. In some (particularly in Man) it is round; that being the most proper Figure for the Position of our Eyes, and the Use we make of them both by Day and Night. In some other Animals it is of a longish Form; in some Transverse[z], with its Aperture large, which is an admirable Provision for such Creatures to see the better laterally, and thereby avoid Inconveniencies, as well as help them to gather their Food on the Ground, both by Day and Night. In other Animals the Fissure of the Pupil is erect[aa], and also capable of opening wide, and shutting up close. The latter of which serveth to exclude the brighter Light of the Day, and the former to take in the more faint Rays of the Night, thereby enabling those Nocturnal Animals (in whom generally this erect Form of the Pupil is) to catch their Prey with the greater Facility in the dark[bb], to see upwards and downwards, to climb, &c. Thus much for the Tunicks.
The next Thing I shall take notice of, will relate to the Humours of the Eye, and that only concerning the Mechanism of the Crystalline Humour; not its incomparable Transparency; nor its exact lenticular Form; nor its curious araneous Membrane[cc], that constringeth and dilateth it, and so varieth its Focus, (if any such Variation there be, as some affirm with great Probability,) nor lastly, its admirable Approach to or from the Retina, by help of the Ciliar Ligament[dd], according as Objects are far off or near, because these Things are what are usually taken notice of; but that which I shall observe is, the prodigious Art and Finery of its constituent Parts, it being, according to some late nice Microscopical Observations[ee], composed of divers thin Scales, and these made up of one single minutest Thread or Fibre, wound round and round, so as not to cross one another in any one Place, and yet to meet, some in two, and some in more different Centers; a Web not to be woven, an Optick Lens, not to be wrought by any Art less than infinite Wisdom.
Lastly, To conclude the Parts of this admirable Organ, I shall make only one Remark more, and that is about its Nerves. And here, among others, the admirable Make of the Optick Nerves might deserve to be taken notice of in the first Place, their Medullary Part[ff] terminating in the Brain it self, the Teguments propagated from the Meninges, and terminating in the Coats of the Eye, and their commodious Insertions into the Ball of the Eye, in some directly opposite to the Pupil of the Eye, in others obliquely towards one Side[gg]. But most of these Things have been treated of, and the Convenience hereof set forth by others that have written of God’s Works. I shall therefore take notice only of one wise Provision the Creator hath made about the Motion of the Eye, by uniting into one the Third Pair of Nerves, called the Motory Nerves[hh], each of which sending its Branches into each Muscle of each Eye, would cause a Distortion in the Eyes; but being united into one, near their Insertion into the Brain, do thereby cause both Eyes to have the same Motion; so that when one Eye is moved this way and that way, to this and that Object, the other Eye is turned the same way also.
Thus from this transient and slight View (I may call it) of the Parts of the Eye, it appears what an admirable Artist was the Contriver thereof. And now in the
Seventh and last Place, Let us consider what Provision this admirable Artist hath made for the Guard and Security of this so well formed Organ[ii]. And here we shall find the Guard equivalent to the Use and Excellency of the Part. The whole Organ fortified and fenced with strong, compact Bones, lodged in a strong, well made Socket, and the Eye it self guarded with a nice made Cover[kk]. Its Humours, and its inward Tunicks, are indeed tender, proportionate to their tender, curious Uses; but the Coats without, are context and callous, firm and strong. And in some Animals, particularly Birds[ll], some Part of those Tunicles have the Nature and Hardness of Bone or Horn.
But for Creatures, whose Eyes, like the rest of their Body, are tender, and without the Guard of Bones; there Nature hath provided for this necessary and tender Sense, a wonderful kind of Guard, by endowing the Creature with a Faculty of withdrawing its Eyes into its Head[mm], and lodging them in the same Safety with the Body.
Thus have I survey’d this first Sense of Animals, I may say in a cursory, not accurate, strict manner, considering the prodigious Workmanship thereof; but so, as abundantly to demonstrate it to be the Contrivance, the Work of no less a Being than the infinite Wise, Potent, and Indulgent Creator[nn]. For none less could compose so admirable an Organ, so adapt all its Parts, so adjust it to all Occasions, so nicely provide for every Use, and for every Emergency: In a word, none less than God, could, I say, thus contrive, order, and provide an Organ, as magnificent and curious as the Sense is useful; a Sense without which, as all the Animal World would be in perpetual Darkness, so it would labour under perpetual Inconveniencies, be exposed to perpetual Harms, and suffer perpetual Wants and Distresses. But now by this admirable Sense, the great God, who hath placed us in this World, hath as well provided for our comfortable Residence in it; enabled us to see and chuse wholsome, yea delicate Food, to provide our selves useful, yea gaudy Cloathing, and commodious Places of Habitation and Retreat. We can now dispatch our Affairs with Alacrity and Pleasure, go here and there as our Occasions call us. We can, if need be, ransack the whole Globe, penetrate into the Bowels of the Earth, descend to the bottom of the Deep, travel to the farthest Regions of this World, to acquire Wealth, to encrease our Knowledge, or even only to please our Eye and Fancy. We can now look about us, discern and shun the Precipices and Dangers which every where enclose us, and would destroy us. And those glorious Objects which fill the Heavens and the Earth, those admirable Works of God which every where surround us, and which would be as nothing to us, without being seen, do by means of this noble Sense present their Glories to us[oo], and fill us with Admiration and Pleasure. But I need not expatiate in the Usefulness and Praises of this Sense, which we receive the Benefit of every Moment, and the want, or any defect of which, we lament among our greatest Misfortunes.
Leaving then this Sense, I shall proceed to the other four, but more briefly treat of them, by reason we have so ample a Sample of the divine Art in the last, and may presume that the same is exerted in all as well as one. For a Demonstration of which, let us in the next Place carry our Scrutiny to the Sense of Hearing.
