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class of all. There are four thousand of up in their stead. They are wrong because them, and they must have a police permit they are unjust and insufficient; because for their trade. They guard their " walks” men who work ought not to need charity; as jealously as monarchs guard their em- because almsgiving to those who by nature pires, and wo to the rag-fox who should and right ought to be independent of all but prowl out of bounds! They live chiefly on their own industry, is in itself an engine of what they pick up-on vegetables found by demoralization and the confession of a sothe gardens of the surburbs, and on fish and cial wrong. The low rate of wages, the meat cast out of the market-stalls. They low range of education, the non-recognition smoke the half-consumed cigars found in the of the divine truths that labour has the right streets, and they drink water flavoured with to its full reward, and that men have the vinegar. They are a wretched, destitute, so- right to labour, the setting up of present cially degraded class, and the sooner a good social conditions as of unchangeable force, system of drainage swept them out of Paris and the preferring to continue a natural the better.

crime rather than disturb artificial arrange

ments—these are the real causes of our preFrom the large mass of evidence collected sent evils; and until we have courage to atby M. Le Play but one conclusion can be tack them boldly, we shall see no amelioradrawn; that, from some cause or causes, tion. We cannot return to the effete systhe whole of the western working world is tems of serfdom, patronage, close guilds, in a painfully unjust and disjointed condi- and other forms of dependence on the one tion. * We may differ from our author as hand, and of power on the other. The to the causes of that condition; we may workman is now free, and will not allow differ still more as to their remedy; but we the chains he has shaken off to be laid on cannot deny the fact, that such a state of his strong right hand again. Our only rethings exists as is discreditable to our civili-medy now is to raise his social and intelsation, and a practical disproof of our Christ lectual condition into parity with its politicianity. The eastern and northern artisans, al importance, and to make him worthy to with whom is neither enterprise nor ambi- exercise the influence which belongs to him tion, neither extended commerce nor indivi- by right. We ought not to have said “to dual liberty, are far better off for all material raise him," but rather to give him space and comforts than our own, in the heart of our power to raise himself. For though much rich, free, powerful countries. Seeing this, is talked of the perfect political freedom-if M. de La Play finds it the shortest way to not always political power-of every man in lay the blame of his indigence on the liberty England, we all know what stringency our of the workman ; partly under cover of de- social laws possess, and how difficult it is siring to see a more friendly hand extended for any man to overcome the prejudices or to him by his master, partly with the ex- the fashions of the day. The workman is pressed opinion that the liberty of the peo- not yet recognised in his true and distinctple tends to the evil of a nation. In a word, ive class, as, in the birth-hour of the old he would throw society back into its past burgher class, he to-day, as they then, is conditions, and restore the systems proved met by the full resistance of all existing by experience to be insufficient. He makes prejudices. When he shall have overcome the pauperization of the lower classes in these, he will have found his true place in the France to rest on the infinite division of world. land, on universal suffrage which gives un We subscribe to the necessity of the due political importance and awakens un noblest amount of self-control; yet we rehealthy political excitement, on the love of pudiate the belief of our present partial polpleasure, and on the decay of subventions or itical economists, that the subjugation of privileges. In England, it is the isolation every instinct, the denial of every natural of the people from the upper classes, public desire, can alone elevate the artisan. This charities, the poor-laws, large families, and is what justice demands should not be nesensuality, that he takes as the concrete cessary; the free full life, under proper recause of all our ill. In these items he is gulations, that nature meant all men to live, right, though even then imperfect. The iso- is what we claim for the artisan as for the lation of the people from the upper classes aristocrat. It is not just that a man should is not to be bridged over by the condescend-deny nature in order to exist on this earth ; ing kindness of patronage or by the re-es- that he who supplies the lives of others tablishment of seigneurial rights; and cha- should himself be destitute. The enormous rities, whether supported by private dona- power of capital is again a matter needing tions or recognised by the laws, are not to thought and regulation--for liberty must be abolished until something better is set be respected with one as with the other.

But when our machinery shall have still ternal world, the form, the colour, and the further developed itself and assumed powers other properties of matter, the sense of sight undreamt of now, when men shall be able is the most important, whether we view it to go back to the same conditions, with im- in reference to the extent of its range, the proved accessories and larger powers, as value of its lessons, or the structure of its gave them honour and independence before, organs. With the senses of Touch and then we shall find that this unhealthy pre- Taste, we are brought into immediate conponderance of capital will subside, and that tact with the objects of our examination. the diffusion of power will lead to the diffu- With the organ of Smell, we inhale from a sion of wealth. Does not this phrase-tak- short distance the radiating or the floating ing it as educational, political, or social effluvia. The sound of the troubled ocean, power-contain the whole enigma? or of the gale which disturbs it, or the thun

We grieve that M. Le Play should have der which rolls above, is heard from afar : written his book, or rather have published But the eye carries us to the remotest horiit under such imposing auspices as those zon around, glances upward beyond the under which it has appeared. Containing, voiceless air, through the planetary regions as we believe, radical and dangerous error, where worlds are but stars,—through the we lament that the Government of such a sidereal zones where suns are too small to nation as France should have leant it the be seen, and to that more distant bourne colour of its sanction and adoption. The where Imagination droops her wings, and theory which France has spent so many Reason ceases to be our guide. But even years and spilled so much of her best blood in these distant realms, where the intellectto solve, has not been solved therein; no ual eye becomes dim, the human eyeball return to feudal tutelage will save the work- exerts its powers,—descrying and describing man of the nineteenth century. Onward— what is there; and if a limit has been asimproving our present material--making signed to the physical creation, it may yet machinery subservient to intelligence, not convey to the human brain the impression only to capital—the wide gulfs lying now of the remotest ray which streams from the between our various social castes bridged very verge of space. over by greater equality in education-the Our visual powers still maintain their pretrue, radical, entire elevation of the work- eminence, when we study the organizations man, not his degradation—these are our of the microscopic world,--the form and only means of getting out of our present functions of atomic life, or the larger strucdifficulties; and these are the means which tures of the creations around us. The M. Le Play decries and disbelieves :-to human ear is deaf to the cry of that life uphold Russian serfdom and Austrian tutel- which we crush beneath"our feet, and to the age instead.

joyous sounds of the living myriads which sport in the sunbeam. The senses of Taste and Smell give us no information respecting the animalcular world; and the rude touch

of man, could it reach the invisible atom, Art. IV.-1. Vision in Health and Dis would fail to disclose either its outline or its

ease ; the value of Glasses for its Restora- properties. The sight alone pierces into the tion, and the Mischief caused by their dwellings of animalcular life, expands the Abuse. By ALFRED SMEE, F.R.S., Sur-material atom into a world, -lays open the geon to the Bank of England, &c. Lond. prolific cells of vegetable and animal organi1847. 8vo. Pp. 64.

zation, and displays to the astonished in2. The Eye in Health and Disease ; with an quirer the structure of those wonderful

Account of the Optometer for the Adapta- tissues which cover the fountains of intellect. tion of Glasses for Impaired, Aged, or ual and animal life. Defective Sight. By ALFRED SMEE, F.R.S., Nor does the superiority of Sight to the &c. Second Edition, to which is append- other four senses seem less striking, when ed a Paper on the Stereoscope and Bino- we consider what would have been the con

cular Perspective. Lond. 1854. Pp. 99. sequences had we been limited to one. A 3. Théorie de l'Eil. Par L.L. VALLEE, great modern poet has described a state of

Ancien Elève de l'Ecole Polytechnique, the world, in which
Officier de la Legion d'Honneur, &c.
Paris, 1844-1846.

“ The bright sun was extinguished, and the stars

Did wander darkling in eternal space, Of all the Five Senses-the sight, the hear

Rayless and pathless, and the icy earth ing, the touch, the taste, and the smell, by

Swung blind and blackening in the moonless which we acquire our knowledge of the ex

BYRON.

air."

But he has not ventured to conceive a world | darkness around, or whose genius and intenanted with sightless occupants, or revolv- dustry had procured new powers or new ing in space which no ray could traverse. luxuries to their race. But whatever might Were our food and our drink tasteless, and have been his advances, either in material or no fragrance breathed from the plant or the intellectual progress, the useful arts would flower, hunger and thirst would still be as have been slowly and imperceptibly devesuaged, and the lily and the rose would de- loped, and his highest pleasures would have light the eye. Were the chords of the lyre been derived from the luxuries of music, and struck in vain, and the voice which soothes the productions which administered to the or alarms us mute for ever, the harmony of senses of Taste and Smell. colours would replace, however imperfectly, From these speculations, which, however the harmony of sounds, and the expression uninstructive, sufficiently establish the value of the human face would still utter, however and superiority of the sense of sight, we inarticulately, the language of reproof or of proceed to give some account of the organ love. Without the ear man could have held by which it carries on its operations, -of communication, and interchanged his labour, the optical changes to which it is subject, with his fellow, however distant he might of the means by which they may be corbe. Though the rattle of the iron wheel rected ---and of the remarkable phenomena, were inaudible, and the watchman deaf to normal and abnormal, which the eye exhibits the shriek of the steam-pipe, the coloured either by the direct action of light, or by beacon would have guided him in his flight; those other agents which exercise an indirect and the pilot might have conducted bis ship influence over the seat of vision. In discussround the globe, though he heard not the ing these various subjects, we mean to adhowl of the gale which shattered his rigging, dress ourselves to the general reader,—to nor the roar of waters which threatened to consider the eye simply as an optical instruengulf him.

ment, and to avoid all questions anatomical, It is difficult to imagine the condition of a medical, or surgical; and we shall not gain world where space is impervious to light, or our object if we fail in making our observaman insensible to its impressions. In such tions popular, and of considerable advanan inquiry the poet might be as safe a guide tage to those who value their sight. as the philosopher, and we would not lose While the eye surpasses all the other inuch did we rest satisfied with the general organs of sense in the extent of its range, it idea in the poet's exclamation, though it was enjoys the exclusive privilege of seeing very not intended to convey it:

distant objects long after they have ceased

to exist. If a fixed star is destroyed, or *Oh what were man—a world without a sun !" ceases to give light, it will, according to its

distance, continue visible for years or for cenWithout any knowledge of the form or turies, till the last ray which it has projected size of his own world, or of the worlds be- has conveyed to our eye the fact of its dis yond it, like the Proteus of the subterranean appearance, or of the extinction of its light. lake, or the mole working in the dark, man Nor are these powers of observation dependmight subsist on the spontaneous productions ent on the magnitude of the eye-ball, or of of the soil, plucking the fruit which he did any of its parts. The minutest eye of the not plant, and gathering the seed which he minutest animal, which itself requires a did not sow, but his sustenance would have microscope to make it visible, contains in been more precarious than that of the world the invisible image which is painted on its of instinct as now placed under his power. retina, a representation of the external world, With the cunning of his fingers, and the -of the earth, and of the ocean, and of the grasp of his hand, and the vigour of his arm, planetary and starry firmament, as distinct and the force of his intellect, he might have and as large when transferred outwardly by sheltered himself from the elements within the laws of vision, as that which is seen by walls of stone, and defended himself against the eye of man, or by that of the elephant enemies, rational or irrational, and equally or of the whale. helpless with himself. His houses might While the human eye has been admired have been grouped into cities, his cities into by ordinary observers for the beauty of its communities, and his communities into na form, the range and quickness of its movetions. His reason might have led him to a ments, and the variety of its expression, it knowledge of the great first cause, and though has excited the wonder of philosophers by he had neither sun nor moon nor stars to re- the exquisite mechanism of its interior, and present the beneficence which surrounded its singular adaptation to the number of purhim, he might have deified the most gifted poses which it has to serve. The eyeball is of his race who had pierced deepest into the nearly globular, being of a spheroidal form

like an orange, its smallest diameter being than before, and is placed in a thin capsule that which we direct to objects when we wish or bag immediately behind the iris, the to see them most distinctly. It moves in a pupil or opening of the iris being opposite socket elegantly prepared for its reception, the central part of the lens. and lubricated by a peculiar secretion, which The crystalline lens is a beautiful piece of entirely removes the friction, and conse- mechanism, and merits a particular descripquently, the irritation with which its motions tion. In its perfect state it is as transparent would have been otherwise accompanied. as a drop of water, and yet it consists of a By means of six muscles attached to it, it great number of coats like an onion, each can direct itself, without moving the head, to coat or lamina being composed of an imalmost every point of a hemisphere; but mense number of fibres, with teeth on each when the motion of the head or body is com- side, like those of a saw, the teeth of one bined with that of the eyeball, it can com- fibre entering into the hollows between the mand almost a continuous picture-a pano- teeth of the adjacent fibres, so as to bind rama of everything around it.

them together. These fibres, which are of The ball of the eye, about nine-tenths of equal length, taper from each end to their of an inch in diameter, is formed externally middle, and they are so combined that the by a tough and opaque membrane, called the lens is most dense in the centre, becoming sclerotic coat, which forms the white portion. less and less dense towards its circumferInto this coat, and in the front of the ball, ence. In the human lens the structure of and slightly raised above it, is inserted a the fibres, and their arrangement, is not so circular transparent portion like a small distinctly seen as in the lenses of fishes and watch-glass, which is called the cornea, and quadrupeds, and therefore we shall describe though as transparent as glass, it is like the generally their structure and arrangement sclerotic coat, so tough in its nature as to in these animals. In the lens of a cod, fourresist powerfully any external injury. It is tenths of an inch in diameter, there were, composed of several firmly adhering layers according to the observations of the writer of equal thickness, and is very nearly half an of this Article, who first discovered the exinch in diameter. Within the cornea, and in istence of teeth in the fibres, the following contact with it, is the aqueous humour, a number of coats, fibres, and teeth :transparent fluid, which has received its name from its resemblance to water. It has Fibres in each lamina or spherical the form of a plano-convex lens, the convex

coat,

2,500 side being the inner surface of the cornea, Teeth in each spherical coat,

Teeth in each fibre,

12.500

31,250,000 and the plane side the visible surface of the Fibres in the lens,

5.000,000 Iris, a flat circular membrane, with an aper- Teeth in the lens,

62,500,000,000 ture in its centre called the pupil. The colour of the eye resides in this mem. Or to express the result in words, the lens of brane, and the pupil has the remarkable pro- a small cod contains five millions of fibres, perty of contracting in strong lights from and sixty-two thousand five hundred milone-fourth to one-eighth of an inch, and of lion of teeth, exhibiting a specimen of meexpanding again when the light is diminish- chanism which may well excite our admiraed. This membrane divides the interior of tion, the eye into two very equal parts, called the In the cod and some other animals, the anterior and the posterior chambers. The fibres terminate in two opposite poles like anterior chamber, which is in front of the the meridians of a globe; but in the salmon iris, contains the aqueous humour, and the and hare they terminate in two septa or posterior chamber, which is behind it, con- lines oppositely situated at each pole, while tains the vitreous humour and the crgstalline in quadrupeds they terminate in three septa lens. The vitreous humour, which resembles inclined 1200 to each other, the septa at one the white of an egg, fills up a great portion pole being inclined 60° to those at the of the eyeball, and keeps it in a state of dis- other, tension, resisting pressure like a bladder, or Behind the vitreous humour, but not next an India-rubber ball filled with water. It is to it, and lining the inner surface of the contained in a capsule or bag divided into sclerotic, is the choroid coat, a delicate several cells or compartments, the humour membrane, covered on its posterior surface occupying each cell as honey does the cells with a black pigment, and immediately of the hoi.ey.comb. The crystalline lens oc-within this pigment, and close to it, is the cupies the front of the vitreous humour, and retina, which is the innermost coat of all, is suspended at its circumference by the next to the vitreous humour. It is a deliciliary processes fixed to the sclerotic coat.cate reticulated membrane, consisting of It is a double convex lens, more convex behind several layers of different structures, the ex

act nature and use of which have not been that if we take an opaque hollow hemisphere determined, although the membrane which the size of the eye, and after making a pinthey form is that which receives the images hole in front of it, replace the back of it of external objects, like the grey glass in with a piece of grey glass or oiled paper, the camera obscura. If we draw a line inverted images of all objects in front of it, through the centre of the pupil and the cen- when strongly illuminated, will be distinctly tre of the crystalline lens, it is called the painted upon the glass or paper. If we now axis of vision, or the optical axis of the eye, take the eye of an ox, of the same diameter and the point where it touches the retina is as the radius of the opaque hemisphere, and called the extremity of the axis. About pare away with a sharp knife the white one-tenth of an inch from the extremity of sclerotic coat till it becomes semi-transthis axis, in a horizontal direction, the retina parent, we shall see painted upon it inverted is slightly raised, and this is the place where images of all objects in front of it, and the optic nerve from the brain enters the having nearly the same size, though more sclerotic coat, and expands itself into the luminous and distinct, as those formed by retina. At the extremity of the axis there the pin-hole in the artificial hemisphere. is a small spot with a yellow margin, which, Let us now see how an inverted image, though called the foramen centrale, may in the human eye, is necessary to show obnot be a real opening, but merely a spot jects erect, or in their natural position. more transparent than the rest of the retina, When rays proceeding from an object enter owing to its being free from the soft pulpy the pupil of the eye, they necessarily fall in matter of which the retina is principally different directions upon the retina; but it composed. This spot, which exists only in is a law of vision, determined experimentalman, monkeys, and some lizards, is from ly, that whatever be the direction in which the thirtieth to the fiftieth part of an inch in the ray strikes the retina at any point, it . diameter, and subtends an angle of about 41 gives us the sensation of vision in a direction degrees at the centre of the eyeball, or the perpendicular to the retina at that point. centre of curvature of the retina.

This law is called the Law of visible Direction, Before we proceed to show how vision is and enables us to explain all the phenomena performed by an eye thus constructed, we of inverted vision, and of vision with one must state three facts ascertained by experi- and two eyes, in the most perfect manner. ment. 1st, Rays of light proceed in straight In the case of the artificial eyeball, where lines and in all directions, from every point the rays always fall perpendicularly upon of visible objects, and illuminate with their the ground which receives them, the point own colour any colourless body or surface of the object from which they issue will be on which they fall; 2d, If we suppose a seen in its true place, along the very line of soldier to be dressed in a red cap, a yellow the ray; but, in the human eye, on account waiscoat, and blue trousers, rays of all these of the refraction of the lens, a ray proceeding three colours will fall upon a sheet of white from any point of an object is not referred paper held in front of him; but the paper back from the retina to the very point from will appear neither red, yellow, nor blue, which it came; but the difference is so small because every part of the paper is illumina- that we see every point of an object very ted with all the colours; 3d, But if we place nearly in its true place. Hence it follows, the soldier in the street, and opposite the that the cap of the soldier must be painted

1 window-shutter of a dark room in which on the lower part of the retina, and will be there is a small hole, and hold a sheet of seen upwards in the direction nearly in paper a foot or two behind the hole, we shall which the ray from it struck the retina, see on the paper a picture of the soldier in- while the trousers of the soldier will be verted. The red rays from his cap will painted on the upper part of the retina, and pass through the hole, and fall upon the will be seen downwards in the direction lower part of the paper, the blue rays from nearly of the ray which came from them. his trousers will fall upon the upper part of The difficulty which has been generally exthe paper, and the yellow rays from his perienced in understanding how we see waistcoat will fall upon the middle part of objects erect when the pictures of them on the paper, thus painting a rude picture of the retina are inverted, has arisen from the the soldier. If the hole be so small as that erroneous notion that the mind contemplates made with a pin, the picture will be very the inverted picture. But we know nothing distinct, though dark; but if the soldier about the mind or its position in judging of were illuminated with the light of a bright sensations, and we must be content with the sun, a photographic picture of him might be indication of the law established by experitaken in this manner.

ment, that any part of an object is seen in a From these observations it will be seen, direction perpendicular to the portion of the VOL. XXVI.

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