teeming with abounding riches. The poor Turk, misgoverned and with no protection against the lawless pillager of his crops, can hardly be blamed for his careless and shiftless cultivation; but as the Indian was compelled to give way to the white race, so must the Turk give way and permit a more faithful hand to cultivate the soil he has neglected. We, of course, do not favor the propagation of Christian civilization by the sword, neither do we believe that any nation has the right to block the way of its advance; nor will the spirit of the nineteenth century much longer permit such a blockade. Whatever or whoever opposes must yield or be crushed. where. Nor can Turkey much longer resist the mighty influences everywhere at work. We deem it not an idle assertion that, within the life of the present generation, Eastern Europe and Western Asia will become essentially what Central and Western Europe are to-day. For the accomplishment of this great renovation there are many fitting agencies; the wonderful activities of commerce, developing channels of communication wherever channels are needed, surmounting difficulties hitherto deemed insurmountable, penetrating regions remote and apart, spanning oceans, delving mountains, and bringing the ends of the earth into easy and quick connection. But there is yet another and a quicker agency to be applied-the outpouring of the strong and vigorous energies of Russia upon and through the weak and enfeebled races that now are the curse of that vast region. We might indulge emotions of regret at the downfall of so intelligent a ruler as the Sultan. Wiser than his people, he has, doubtless, earnestly desired to work the reformation of his nation. Physically and mentally he is a noble specimen of a man, and well deserves a better fate than that awaiting him. We have lately seen, nevertheless, how a grander throne than his may tumble, and how a mightier power than that of the Sublime Porte may collapse and vanish as by the wand of a magician. No government ought to survive the period of its usefulness; no state can prosper whose government is upheld for mere selfish purposes. If the hour of doom for the Ottoman Empire has struck; if the awful sentence, "mene, tekel, upharsin," has been written, the calm judgment of the world must approve the sentence, for the grand progress of the nineteenth century demands the sacrifice. Had it not been for the selfish and mistaken policy of Europe, when its diplomacy in 1840 combined to recognize the integrity of the Ottoman Empire, this "sick man" would long since have been out of the way; again, in 1854, France, in the interest of Rome and England, from a fancied danger to her eastern possessions, checked the advance of Russia. Pent up and restrained within her broad but frigid boundaries, Russia has long wished to push her boundary to the Middle Sea, and to control the channel which opens out from the vast waters of the Caspian and the Black Seas-thus releasing her navy and her commerce now blocked during eight months of every year. The vigorous population of Russia, shut off from the more arable lands and genial skies of a southern latitude, once liberated would press forward with an irresistible force over the fair lands of South-eastern Europe; but, unlike that rude northern horde, which once rushed upon effeminate Rome, merely to waste and destroy, the Russian, with his habits of sssssful and nationt industry would pation of Con erinction of the Earpe. Should th trong reasons to startinople wor te of influences there: they would Damascus, and nated by a p the hallowed as With that renown red to the Chri Fuld soon reveal ng guarded b With the question of bad faith, involved in the recent diplomatic papers issued from St. Petersburgh, we have nothing to do. From this action of Russia we simply aim to draw conclusions and results. Russia has wisely chosen her time for action-and while conferences may be held, her armies are on the march and her navy is afloat. Europe to-day has no power to internose Russian occupation of the -and all Pa pase of an inf in become the k and honey. Those laughing not be the fa ke gift of vis ed in the g why shall dall our senses of Constantinople and the of the Ottoman power in hould this occur, as we have ons to believe it will occur, ople would become the cenuences that would not stop y would reach to the gates us, and Jerusalem, so long by a power so unsuited to ed associations connected renowned city, would be he Christian world. Science reveal the buried mysteries arded by superstitious bigall Palestine, feeling the an infused energy, might ne the land flowing with ney. We might reasonably indulge in further speculations as to results which would naturally follow a reorganization such as we have outlined. Egypt and Arabia would be brought under healthier influences. Even that vast terra incognita, styled the land of the Turcoman in Central Asia, might soon be opened up. Push the railway and the telegraph into these dark regions and Christian civilization will quickly follow. Khiva, Bockhara, and Samercand may become centers of new enterprises. Surely, whoever has a comprehensive faith in the final triumphs of Christianity, will acknowledge that in some such way must that triumph be secured. THE EYE AND ITS STRUCTURE. BY E. WILLIAMS, M. D. SE, in a series of articles, up to the readers of the ghing orbs that borrow, -e skies, the light they wear." I shall make them spicy sure a hearty rally at each remains as yet in total f I fail in the effort, it he fault of the orbs, wherblame may attach. The f vision, and the exquisite h which it is enjoyed, are r for the pens of angels, Le gorgeous tints of the t in which the universe is urora rides in a rose-colpreceded by the morning ng roses with her lavish all we not enjoy the floral or the eyew we see with? In etive minds have dwelt in s the noblest and the best ses. So long as the soul's e to thrill with emotion, gle in sublime bewilder all light and joy, that long will its reputed window remain an object of admiration and wonder. See it pivoted in its secure bony orbit, sweeping the heavens and drinking in their intoxicating glories, the most marvellous organ, both in its structure and functions, of the whole organism! Mystery of mysteries-so complex in its parts, so far-reaching, and yet so simple and easy of use! He that hath eyes to see, let him see, and let him look out lest he undervalue this divine orb and extinguish its "holy light." "To open our eyes at present is not to have a simple feeling; it is, as it were, to have innumerable feelings. The color, the magnitude, the figure, the relative positions of bodies are seen by us at once. It is not a small expanse of light which we perceive, equal merely to the surface of the narrow expansion of the optic nerve. It is the universe itself. We are present with the stars, which beam upon us at a distance, that converts to nothing the whole wide diameter of the planetary T hinda us down to the globe in which we dwell, belonged only to our other senses, and has no influence over this, which even in its union with the body, seems still to retain all the power and unbounded freedom of its celestial origin." of isolated points, for seeing each one To get, in this way, an idea of the whole blue vault, The eyes of animals may be arranged in two great classes. In the simplest form its power is limited to the mere perception of light. The lowest and most insignificant creatures, but a step removed from the vegetable kingdom, present, in some instances, what are called eye-dots, composed of a special nerve, whose peripheric extremity is exposed to the action of light through These merely its transparent skin. discern light from darkness. Others, perfectly transparent and without any trace of optic nerve or appearance of eyes, seem to feel the influence of light, some seeking and others shunning it. Whether they are really sensitive to light, or only respond to the rays of heat that are always associated with it, it is impossible to determine. lebeate internal sc or the sclerotic i the sheath of the o tent the size of a meets the eye wit Dediately within th delicate pigment forms the part of he camera obscura my be so aptly con membrane, called th perforated behind ad is continuous in tain, which lea vhere it joins the pendicularly thr irus a septum ered in the cente the pupil whi regulates the a ed to the botto is so called fro alar and form, t denominated in the seat For the study of the wonderful phenomena of vision, a knowledge of the structure of the eye is indispensable. As it is with human vision that we are most interested, I will commence with a short description of the human eye, referring to the peculiarities of the eyes of other animals, as we proceed, by way of comparison. The organ of vision proper, is the spherical ball called the globe of the eye. accessory parts are muscles to move it, lids to protect, and a lachrymal gland to moisten and keep it in a healthy condition. When we examine the eyeball, there are two parts that fix the One is the front attention at once. In higher orders of animals the eye assumes a more complicated form, capable not only of taking cognizance of light, but of distinguishing forms. This is vision. To secure this end, the light issuing from distinct luminous points must be separately perceived. Each nerve-filament must no longer be flooded with light coming from all directions, but only receive that which emanates from a given point in space. To each nerve-fiber, therefore, corresponds a certain field of vision. In proportion as these elementary fields of vision become smaller and more numerous, does the eye become capable of seeing more and more minute parts of the objects around us. At last, in the most perfect form of the organ, each of the elementary fields of vision, which together measure the whole scope of sight, is infinitely small as compared with the total visual field. In turning the eye towards the sky, for instance, the portion of the concave vault, which it takes in at once, is called the field of vision. This surface may be consider The The iris is clear portion, resembling a watch crys- felor in different ghter accordin ark pigment in it ck, languishing poetic as t mply upon the ches of the di andless liberali et, is not confi never been a Lave said the iris ter called the ned from the of own face, see me oks closely in pupilla, ild A popula sentimental turn these words: e ernal scructures. Postesclerotic is continuous with of the optic nerve, a cord size of a crow quill, which eye with the brain. Imwithin the sclerotic coat is pigment membrane, which e part of the black paint in obscura, to which the eye ptly compared. This thin called the choroid coat, is behind by the optic nerve, auous in front with a dark ich leaves the sclerotic ns the cornea, and passes rly through the eye. It ptum or inside curtain, e center by a round openil which, by its varying es the amount of light ade bottom of the eye. The led from its resemblance, form, to a rainbow, and is ted in most languages. e seat of the great variety fferent eyes, and is darker cording to the amount of at in its texture. Piercing ishing blue, or crocodile as they sound, depend the heavier or lighter he divine Painter, whose berality, in one race at confined to the iris, ano en appreciated! But I e iris has a hole in the the pupil. It was so the diminished image of e, seen in the pupil when ely into another's eye, the , meaning a diminutive pular poet once gave a urn to this phenomenon 5: eyes, my blushing fair, thyself reflected there, ze on thine I see iniatures of me." to the choroid, I must -tailed description of that nects with the iris and ards near one-quarter of thicker as it nears the iris, and forms a wedged-shaped zone, the thick edge ending in front in sixty or seventy rounded points, which present inwards towards the line of vision and surround the margin of the crystalline lens like a corona. This whole thickened part is called the ciliary body, and the points the ciliary processes. The most interesting part of this body is a delicate fan-shaped muscle, the ciliary muscle, which performs the duty of varying the focus of the eye to suit it for distinct vision at different distances. It is the muscle of accommodation, and by its action, varies the curvature of the lens. Like all muscles it has its fixed and its movable point or points, or its origin and its insertion. It is fixed to the inner surface of the sclerotic and corneal junction, in a complete circle, and sends its diverging fibers, some backwards to become fixed in the choroid, and some inwards into the thickness of the ciliary body and processes. Attached to the ciliary processes, and passing inwards to the edge of the lens, all round, is a delicate membrane, the suspensory ligament of the lens. From the position of the ciliary muscle, it can act on the shape of the lens, through this connection, by tightening or relaxing the lig ament. The third tunic, from without inwards, and that which constitutes strictly the visual membrane, is the retina. It is said to be the expansion of the optic nerve, which pierces the sclerotic and choroid behind. It contains, however, an apparatus, additional to the nerve-fibers, for the specific purpose of perceiving light. The minute anatomy of the retina is so exquisitely beautiful and so instructive, that I must postpone its description for the present, confining my remarks to the distribution of the retina. It extends from the optic nerve forward, as a delicate, transparent nerve-membrane, to a point in front of the equator of the globe, near one-fourth of an inch back of the base of the cornea. Its distri to which light can reach it through the pupil. Looked at from the front, the retina forms a sort of cup, with its hollow part presenting forwards, ready to receive the rays of light. great clearness. The cornea, the aqueous, the lens proper, and the vitreous humor constitute a double convex lens, whose principal focus is at its posterior surface, on the concave disc of the retina. By this arrangement a distinct, small image is formed on the retina of any landscape or other object to which the eye is directed. This image makes an impression on the sensitive retina, which is conducted by the fibers of the optic nerve with the velocity of lightning to the brain, where consciousness is enforced, and we see. The annexed cut (Fig. 1) represents The three tunics mentioned, lie in immediate contact one within the other, the sclerotic forming the outer, the choroid the middle, and the retina the inner; the cornea completing the containing tunics anteriorly. Filling the whole interior, and distending the globe, are the so-called humors of the eye. They, like the cornea, are perfectly clear, like the clearest glass, and allow the free passage of light through them to the retina. The back fourfifths of the globe is filled out by a jelly-like fluid, called the vitreous bumor, over the convex surface of which the hollow concavity of the retina is expanded. Lodged in a depres.sion, in the anterior central part of the vitreous, is the crystalline lens, a 'double convex body, similar in shape to a sun-glass, of a firmer consistence than the vitreous, and enveloped closely in a clear, thin bag, the capsule of the lens. From the margin of the lens, in its entire circumference, which is a smaller circle within the corona of the ciliary processes, proceeds a membraneous attachment to those processes. Thus the lens, with its suspensory ligament and the ciliary processes, are so connected that they form a complete septum or partition through the front of the eye, close behind the iris. The space in front of the lens, between it and the transparent cornea, is filled with a liquid, called the aqueous humor, from its exact resemblance to water. The iris being bathed on all sides by this liquid, is free to move without friction in the frequent and rapid variations in the size of the pupil. These transparent humors, including the cornea, form a system of lenses (or taken together they are one lens) placed just in front of the retina to collect and concentrate the light upon it. They are termed the dioptric FIG. 1. Br. The r an of the ir site the cente ht that en Barily pass th The subjoined Estate how the tA(as a car a section of the globe, with all its parts in position, as they would appear if the eye were frozen and cut through the center, and the point of entrance of the optic nerve. The cornea c is more curved than the rest of the globe, the iris i being attached at its base. The sclerotic s, extending from n, the optic nerve, to the base of the cornea, where s, the suspensory ligament, is seen connecting the ciliary body with L, the crystalline lens. The choroid C is seen as a black line reaching from the optic nerve behind to the suspensory ligament, which holds the lens in position, in front. The thickened anterior part of the choroid, which gives off the suspensory ligament, lodges the ciliary muscle. The space between the lens L and the cornea c. is the acqueous chamber and that large red by the tr med positio The modificati fr of the globe internal par es of anima ir peculiar wi the sides of c: both be aimals, who et of the cav change fibe e right side o the retina of a. In fich mach and cros One stick interchang them the |