actions of this wonderful organ, we arrive amidst many mysteries, and must admit that perception is not explicable by laws which govern matter. Here spirit takes the light into its own mystic keeping, and leads man through wonders many, and vastly above the comprehension of the superficial. The Diagram is the same section, though on a less scale than Dr. Franz's. It represents a horizontal section of the anterior part of the head, made in the direction of a line passing through the middle of the anterior aperture of each orbit, to show form of orbit; position of eye-ball; arrangement of muscles; the lachrymal organs; interior structure of globe; course of optic nerve; and formation of the image of an external object on the nervous membrane of the eye by means of the rays of light. The vessels and nerves are omitted. 1 Shows the lateral walls of the orbit. 2 The left eye-ball with five of the six muscles. 3 Is the superior. 7 The superior oblique muscle (with its tendon passing through a loop of cartilage), which is affixed to the foremost part of the upper wall of the orbit, where this wall unites with the interior wall. 8 The lachrymal gland. 9 The conjuntiva, covering a portion of the anterior hemisphere of the globe and the interior surface of the eye-lids. 10 Small orifices, through which the tears pass into the lachrymal ducts. 11 A transverse section of the lachrymal ducts. 12 The ophthalmic artery, as it enters the orbit by foramen opticum. 13 A horizontal section of the right globe. 14 The sclerotica. 15 The cornea. 16 The choroid. 17 The dark pigment. 18 The retina. 19 The iris, having the pupil widely open. 20 and 21 The anterior and posterior chambers containing the aqueous humour. 22 The lenticular system. 25 The optic nerve. 26 The chiasma of the optic nerves (longitudinal section of which is made), the numerous fibrils composing these nerves, their course, and decussation. 27 The part of the optic nerves coming from the brain. 28 An object which reflects the light in the direction of the lines drawn from the points a to the eyes directed towards the object, just as every other point in the object would do. The lines b are pencils of light, as they find entrance through the pupil into the interior of the eyeball, where each of them is by refraction made to converge to a point, called the focus, which, falling exactly on the retina, forms a distinct image thereon of the point a of the external object from which the pencil of light emanated. This is what takes place at least in the eye in its normal state; but when there is any deviation from this state, and the condition of the eye is such as to bring the rays of each pencil of light to a focus at the line c or d, no distinct image can in this case be formed on the retina; since, when the focus occupies the place of the line c, the rays, in meeting the retina, are again divergent; and, when the focus is situated at the line d, the rays, in meeting the retina, are not yet brought into union with each other. The first case occurs in a near-sighted eye, and the second in a far-sighted eye. The lines e represent only the principal rays of each pencil of light reflected to the left eye. The orbit occupies a spherical cavity formed of seven bones, which are quite independent of the fashion of the head-it is rather conical at the back, with apertures for communication with the brain. The ball or apple of the eye is spherical-the most beautiful form in nature-the form which nature assumes in all most pleasing expressions. The vault of Heaven-the rainbow-the contour of woman-the shape of the brow-lash and lid of the eye-the path of the sea— -the sweetest sounds are roundthe marital emblem-the very shape in which the mind always conceives the great Spirit resident-is that of a sphere or circle. It would exceed our limits to say more on shape, else very many pleasing lines might be added. Its motion is aided by its shape; in short, the sphere is the only perfect and independent shape, all other shapes being but parts of it. It is the shape which beauty assumes when it has executed its mission of action and attrition. The eye's imperial eminence above all the other senses gives it dignity and power. The elevated situation yields the idea of a lighthouse, from whence we may look down on the storms and sands of time, whilst we observe the drama of fortune and vicissitude; and, although the very foundations of the sea may be raised in many dusky atoms, yet the lamps of this lighthouse remain faithful and luminous. Nature has built a wall round about this great treasure, i.e., seven bones form a deep cavity, called the orbit, in which rests the ball or apple, with its muscles, vessels, &c. The eye may be said to ride in an adipose substance, as the sea-fowl rides upon the wave. The |