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Curious Formation of the Eye.

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Though these are only conjectures, formed from the little we know of the wonders of nature, yet they are conjectures which fill the mind with awe and reverence, open to it a vast and boundless field of thought, do away the contracted and partial notions we may entertain of ourselves, and tend to soften and ameliorate our hearts.

FEBRUARY V.

Curious Formation of the Eye.

THE eye infinitely surpasses all the works of human industry. Its structure is the most wonderful thing the understanding of man can become acquainted with the most skilful artist cannot invent any machine of this kind which is not infinitely inferior to the eye; whatever ability, industry, and attention he may devote to it, he will not be able to produce a work that does not abound with the imperfections incident to the works of men. It is true we cannot become perfectly acquainted with all the art which Divine Wisdom has displayed in the structure of this beautiful organ; but the little that we do know suffices to convince us of the admirable intelligence, goodness, and power of the Creator.

In the first place, the disposition of the exterior parts of the eye is excellent. How admirably it is defended! Placed in durable orbits of bone, at a certain depth in the skull, the globe of the eye cannot casily suffer any injury. The over-arching eyebrows contribute much to its beauty and preservation; and the eyelids more immediately shelter it from the glare of light, and other things which might be prejudicial; inserted in these are the eyelashes, which also much contribute to the above effect, and also prevent small VOL. I.

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particles of dust and other substances striking against the eye.*

" The internal structure is still more admirable. The globe of the eye is composed of tunics, humours, muscles, and vessels: the first coat is called the cornea, or exterior membrane, which is transparent anteriorly, and opake posteriorly; next the choroid, which is extremely vascular; then the uvea, with the iris, which being of various colours, gives the appear. ance of differently coloured eyes, and being perforated, with the power of contraction and dilatation, forms the pupil; and lastly, the retina, which is a fine expansion of the optic nerve, and upon it the impressions of objects are made. The humours are, first, the aqueous, lying in the fore part of the globe, immediately under the cornea; it is thin, liquid, and transparent : secondly, the crystalline, which lies next to the aqueous, behind the uvea, opposite to the pupil; it is the last of the humours, of greater solidity, and on both sides convex: the third is the vitreous, resembling the white of an egg; it fills all the hind part of the cavity of the globe, and gives the spherical figure to the eye. The muscles of the eye are six, and by the excellence of their arrangement it is enabled to move in all directions, Vision is performed by the rays of light falling on the pellucid and convex cornea of the eye, by the density and convexity of which they are united into a focus, which passes the aqueous humour, and pupil of the eye to be

Besides these, amongst the external parts are enumerated the lachrymal gland, which secretes the tears; the lachrymal caruncle, a small fleshy substance at the inner angle of the eye; the puncta lachrymalia, two small openings on the nasal extremities of each eyelash; the lachrymal duct, formed by the 'union of the ducts leading from the puncta lachrymalia, and conveying the tears into the nose; the lachrymal sac, a dilatation of the lachrymal canal.—E.

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more condensed by the crystalline lens. The rays of light thus concentrated penetrate the vitreous humour, and stimulate the retina, upon which the images of objects, painted in an inverse direction, are repre sented to the mind through the medium of the optic

nerves.

Thus we have abundant cause to thank the God of mercy who has so exquisitely formed the eye, and to acknowledge the wisdom, power, and admirable skill displayed in its structure and wonderful organisation. May we never forget the benefits we have received, nor the blessings we enjoy, but ever look up to the Author of our being with gratitude! When we see the various woes and miseries which afflict many of our fellow-creatures, let not our eyes refuse the tear of sympathy, nor our hearts be shut against compassion. May tears of joy flow from every eye, when we receive the renewed proofs of God's goodness and love; and let us rejoice when we are enabled to soothe the anguish of our afflicted brethren, or wipe the tear from the poor and disconsolate. Thus shall we fulfil the design of our Maker, and enjoy the approbation of our God.

FEBRUARY VI...
The Fog.

A MONGST the numerous phenomena which we see in winter, the fog, or mist, particularly merits our attention. It is formed of exhalations, which occupy the lower region of the atmosphere; they arise from the earth, and are condensed by the greater coldness of the surrounding air. During the continuance of a mist, a grey mantle is spread over the face of nature; every object is imperfectly seen and enveloped in

upon us.

obscurity the eye often in vain attempts to pierce the thick curtain; all is confused and indistinct; the rising sun slowly disperses these vapours, which at length are gradually dissipated; his power is confessed, obscurity vanishes before his rays, the surrounding objects are restored to our view, and the heavens resume their wonted light and beauty. The mist is, however, still seen on the earth, but it is close to the ground, or hangs on the roofs of houses; and the horizon, so long veiled from sight, now opens As the face of the earth, before the sun beams upon it, is overspread with fog, dew, and vapours, so once were the blessed regions of science and of knowledge enveloped in the thick mist of ignorance and of superstition; whole countries were obscured, kingdoms obumbrated, and darkness ruled with a leaden sceptre the groveling race that licked and grew fat beneath her chains; whilst error, prejudice, and sloth, so clouded their faculties and benumbed their feeling, that light was not sought for, nor wisdom esteemed; human reason was no more, and innocence had retired. At length the moment arrived when, the measure of their iniquity being filled, the triumph of darkness, of ignorance, and of superstition, was to cease. The sun once more

dawned, and flashed such a steady blaze of light from the horizon, that the gloom, which for centuries had buried man in obscurity, and rendered torpid all his powers, at once fled, overpowered by the fervency of the beams which penetrated her secret recesses, and exposed to the face of day the horrors of her naked deformity. But, because in this day of light and of truth we are much superior to those dark ages in every thing that can dignify and bless human nature, let us not think our work completed, and that we have no more to do. Though emerging from Gothic gloom and Vandalic darkness, the light shines with

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greater brilliancy and power, we are still young in knowledge, and very ignorant of the true and pure tenets of religion, which still labours to throw off the shackles of ceremony and the yoke of superstition, with which the ignorance, the presumption, and the audacity of man has obscured her simplicity and sullied her purity. The blessed period is probably hastening, when an enlightened race of men shall look back upon our generation with as much compassion as we now feel for the victims of oppression and monkish superstition, in what we are pleased to call the dark ages.

FEBRUARY VII.

Of the Tides.

THE greatest part of the surface of the earth is covered with water, which is called sea, and is very distinct from lakes and rivers. These contain more or less water as the season is dry or humid, whilst the vast body of the ocean ever preserves its bulk unaf fected by such contingencies. Twice in the day it ebbs and flows according to certain rules; when at its greatest height on any shore it begins to decrease, which lasts about six hours, and is called the ebb. At the end of six hours it begins again to flow, and continues to increase six hours longer, when it gains its greatest elevation; it then again retires, and rises again in the same space of time: so that in twentyfour hours the sea has twice ebbed and twice flowed.

This regular and alternate motion of the sea is called its flux and reflux, or ebbing and flowing, and constitutes the tides. When it rises and flows towards the coast it is called flux; when it retires from the shore, reflux. These tides are chiefly influenced by

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