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Had Mr. Glaisher been acquainted with Mr. Salom's visometer, he would have given it his highest recommendation. An inequality in the focal length of the eyes is a much more common affection than is generally supposed; and therefore the first duty of an optician is to determine whether or not such an inequality in the eyes exists, and then to ascertain the focal length of the lenses required to equalize them. In a case of this kind, which came under our notice, the inequality was so great as to produce double vision of persons in the street,-an effect which was doubtless owing to an effort of the eyes to obtain distinct vision of one of the persons by getting rid of the other. We sent this person to Mr. Salom, who constructed spectacles with lenses of different focal lengths, so as to make the images in each eye equal, and we have learnt that the duplication of objects ceased to take place.

dwell upon it. I speak this from experi- As almost every person with normal ence, and my personal acquaintance with sight, that is, every person who is not shortgentlemen afflicted with peculiarity of vision, sighted, must, with very few exceptions, rewho in London have found no relief. Since quire the use of spectacles, it is of importhe Exhibition, I have learnt that Simms tance to determine the time when they pays some attention to these points. France should first use them. It is a common pracfurnished one exhibitor, Henri, who seems tice with those who are unwilling to be conto have paid much attention to optical sidered old, to delay the use of glasses as science and its application. I expect one of long as possible. This is a great mistake, the good results of the Exhibition will be an and one most injurious to the eyes. Specendeavour on the part of some opticians in tacles should not only be used the moment England to meet this want." they enable us to read or to work more easily, but as the eyes become more longsighted with age, new and deeper glasses should be substituted. The eye is an organ of too delicate a structure to be rudely used, and it cannot with impunity be exposed every day to a constant strain, striving to see what is beyond its power, to pry into what is too minute, or to decipher what is indistinct or confused. There are many objects to which our attention is called, when our spectacles fail to give us their usual aid. In looking at maps, for example, a reading-glass is absolutely necessary, and if it is used along with our spectacles, it will be found to give a peculiar relief to the eyes, and will be often used in reading books in small type, for which our usual spectacles have not sufficient power. These reading glasses must, of course, have a greater diameter than two and a half inches, and though each eye necessarily looks through the margin of the Although spectacles may be required for lens, there is no perceptible indistinctness in reading, or for every kind of work executed the vision. When used alone without specby the hand, they may not be needed for tacles, which we do not recommend, Mr. greater distances. In general, however, Smee has denounced them as extremely inwhen spectacles have been used for ten or convenient in practice, "because," he says, twelve years, and in advanced life, they may "if both eyes are directed to the object be required for examining pictures in a pic- simultaneously, it is either doubled or renture gallery, or public buildings, or even dered very confused, because two eyes canlandscapes, whether within a short distance not regard an object through a lens without of us or more remote. In these cases one its appearing double. Sometimes indeed or two additional pairs of spectacles are re- the impression of one eye is instinctively quired, and in all these the centres of the neglected, and then but one object is seen; glasses must be more distant than those in nevertheless in all cases, and under all cirthe spectacles used for reading, but always cumstances, if we really see any object less than the distance between the centres of through a lens with both eyes simultaneousthe pupils. The spectacles for a picture ly, the two objects must appear in different gallery, or for viewing pictures in private places, and consequently double. In my houses, must have their lenses of a much peregrinations about London, I have been greater focal length than those used for surprised at seeing lenses labelled 'Binocureading, and the same lenses should be used lar, at some apparently respectable shops, in looking through the stereoscope. In old age, a third pair of spectacles for viewing very distant objects, and having very long focal lengths, will be found particularly useful.

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which well indicates the knowledge possessed by even the better order of spectaclesellers." This denunciation of "Binocular" reading-glasses is to us quite incomprehensible. They neither double objects, nor render them confused, and we found them, when used along with spectacles, one of the most

*The Eye, &c., p. 63.

fold into an eye-glass, will be found a very convenient form for out-of-door use, as the eye-glass, having twice the magnifying power of the spectacles, may be advantageously resorted to as a microscope of small power. When we consider the varying intensities of light to which the eye is exposed, from

valuable combinations which optical science any object with one eye, when we have two has presented to the long-sighted community. at our disposal, is to injure both-the one This method of using the reading-glass by too much work, the other by too little. along with spectacles, is equally applicable In the occasional use of an eye-glass the eye to the short-sighted when they wish to see cannot be much injured, especially if it is minute objects, and will be found a valuable applied as often to the one eye as to the auxiliary to persons of advanced age. In- other, but no person who values his sight stead of producing magnifying power by will employ it habitually even with this prereading-glasses, it may sometimes be more caution. A pair of convex spectacles which convenient to have one or two pair of spectacles with lenses much more convex than those we require for reading, or two pair may be used together. This mode of see ing very minute objects is particularly convenient when we require the use of our hands, and we would counsel the artist, as well as the student, never to command the use of the bright summer suns of the south, the his hands by grasping a magnifying glass dazzling white snows of the temperate and with the muscles of his eyebrow. northern zones, to the twilight illuminations The rectangular reading-glasses now made of winter, it is of great importance to the with two cylindrical surfaces at right angles preservation of sight to protect the eye in to each other, an invention imported from the one case, and to aid it, if possible, in the France, are greatly to be preferred to those other. During the last century green glasses with spherical surfaces. With one excep- have been employed to protect the eye from tion, they are not described in any optical work with which we are acquainted, and Mr. Smee does not not seem to be aware of their existence. We have now before us a lens executed for us, above forty years ago, by Mr. Peter Hill, optician in Edinburgh, and we have seen one or two very well made by the London artists.

excessive light, and they are decidedly the best of all coloured glasses, as they absorb the extreme violet and blue rays, and transmit the red, thus producing a shorter spectrum, and consequently a more distinct image on the retina. Fashion, however, always the victim of ignorance, has introduced blue glasses, which, as they absorb The observations which we have made on different parts of the spectrum unequally, spectacles for long-sight, are, generally and transmit the extreme violet and blue speaking, applicable to the short-sighted. rays, are more mischievous than useful. This species of imperfect vision is common- Science, however, the unwearied benefactor ly congenital, or existing at birth. The eye, of an ungrateful community, has substituted however, often suffers remarkable changes for green and blue media, an opaque glass in its focal length during its growth, and of no colour, by means of which we can persons who were short-sighted in early life moderate, in any degree we choose, the light recover from it at a greater age, while those which reaches the eye. In strong lights, who were short-sighted in infancy become so and even in ordinary lights, when the eyes afterwards. Short-sight is most frequent in are tender, it is not enough to diminish the artisans who require to have their work light of the objects which we see. It is of brought near the eye, and in literary men the greatest consequence to get rid of the who are devoted to reading; while shepherds light which enters the eyes at the temples, and sailors, and labourers in the field, have by opaque screens attached to the spectacle their sight lengthened by their profession. frame. We have now before us a pair of 'Like the long-sighted, the short-sighted should have spectacles of various numbers, from those which they require to see their food, or their friends on the opposite side of the table, to those which they require to avoid danger in the street, to see pictures in a gallery, or to enjoy the near or the distant landscape.

In the preceding observations we have taken no notice of eye-glasses, which are seldom used, excepting by those who are ashamed to employ spectacles. To look at

* Art OPTICS, Encycl. Brit., vol. xvi. p. 388.

spectacles made and used by the inhabitants of Greenland, for preventing snow blindness. They are made of wood, and have no lenses. The light is transmitted to each eye through a slit about 2 inches long, and the 50th of an inch wide, and becoming wider at the ends next the nose. Immediately behind each slit, the piece of wood is formed into a small hollow box, the side of which press gently upon the temples, the eyebrows, and the cheeks, so as to exclude all light whatever, excepting that which passes through the slits. The great length of the slits is necessary to give the vision of objects to the extreme

right and left, when the eyeball is turned as far as it can be turned in these directions. But while it is necessary to diminish light of high intensity, it is often as necessary to increase it. In parts of the earth where the nights are long, and the sun's light withdrawn even during the day, so that the inhabitants require the aid of artificial light, it is of importance to discover the resources with which science can supply us. We have long been of opinion that certain rays act more powerfully upon the retina than others, though their illuminating power be less. We have known cases in which the eye, in certain states, is more or less blind to particular colours, not only in persons who are colour-blind, but in persons of ordinary sight when the eye has been previously under the influence of light. We have, therefore, from observation as well as from theory, been led to believe that the yellow rays have a more powerful action on the retina than even white light, and, consequently, that yellow glasses might be advantageously used by those who require increased light either from the nature of their retina, from the profession which they follow, or the climate which they inhabit. When anything is lost in the dark, where no artificial illumination can be obtained, the enlargement of the pupil, either by waiting in the dark till it expands sufficiently, or by the application of belladonna, might enable us to find it, or by means of a lens we might condense the faint light to a certain degree, for it is light more than distinct vision that is required to find anything in feeble light.

In proportion to the assistance which we derive from spectacles, is the misery which we experience in losing or mislaying them, under circumstances where they cannot be replaced. On such occasions we are for certain purposes blind, and there are few persons advanced in life who have not frequently experienced this misfortune. In such a dilemma we may achieve a temporary recovery of our sight by looking, or even reading, through a pin-hole held close to the eye, by making an extempore lens with a drop of varnish, or wine, or even water, laid upon a clean piece of glass, or by placing it on the hollow side of our watchglass; or what is best of all, by crossing at right angles two cylindrical bottles filled with water, and looking through the portion that is crossed.

If the reader has followed us intelligently throughout these pages, and has any faith in the results and deductions of science, he will not fail to watch over his eyesight as the

most precious of his blessings, and he will have saved himself many hours of anxiety, and many years of suffering, if he is so fortunate as to spend the last decade of his life. with his eyes bright, and his vision unimpaired. In the ordinary diseases to which the eye, like the other parts of his body is subject, we may safely confide in the skill of the experienced physician; but in the diseases to which it is liable as an optical instrument, where optical science can alone direct us, we regret that professional assistance is difficult to be found. Guided by practice, the skilful oculist may dexterously extract the crystalline lens, or make an artificial pupil; but all the refinements of optical science are requisite in the practitioner to whom we commit the care of our sight; and we trust the time is not distant when men will be expressly educated for this branch of the healing art, and will exhaust in their practice the rich resources with which science can supply them.

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THE majority of Englishmen who tacitly approve or carelessly defend the existing regime in France, commonly lay out of the account one of its most dangerous and (we fear) utterly irremediable results or concomitants - the exclusion from the public service of almost every trained politician, who, prior to December 1851, had given decided proofs of talent and integrity. To carry out the coup d'état, it was (or was deemed) necessary to place under temporary restraint, with peculiar circumstances of personal insult and degradation, between two and three hundred of the most eminent members of the Assembly which had just been dissolved by violence. Three-fourths of these were not even accused or suspected of intrigues or conspiracies. Their offence was their moral weight, their acknowledged respectability, and their apprehended influence over the popular mind, should they be left free to vindicate the outraged dignity of the constitution. For merely protesting against the illegal force put upon the representative body to which they belonged, or (in some remarkable cases) for merely

being of a temper and character that made at the head of this article. There cannot be such a protest probable, they were conveyed a more convincing illustration of the injusin convict-vans, like felons, to ignoble places tice of our too prevalent mode of talking of confinement; and several of the most about France. He was recently described distinguished were only released upon con- by an eminent northern cotemporary as dition that they should remain in exile until the most passionless, philosophic, and unthe meditated despotism was consolidated prejudiced of Frenchmen -a description and complete. which is verified by the whole tenor of his To bring their case home to English ap- life. He has been more or less before the prehension, let us suppose that, in the spring public for nearly forty years. He has 1855, when representative government was written largely on a great variety of subat a discount, some scion of royalty, or any jects-literary, artistical, philosophical, and other reckless pretender, in combination political. The invariable tendency of his with the cleverest frequenters of the Turf productions has been to purify taste, to Club, had debauched the household troops diffuse and dignify truth, to elevate intellecby gratuities or promises, surrounded both tual pursuits, to uphold principle, and prehouses of parliament, turned back all who serve order. Both as an author and a attempted to enter, and packed off all who politician, he has been invariably found cohad ever risen above mediocrity in debate operating with the most cultivated, enlightor acquired any hold on opinion in any way, ened, moderate, and respected amongst his to Newgate, Coldbath Fields, or the Mill- countrymen. He was elected, with univerbank Penitentiary, in those gloomy vehicles sal approbation, a member of the Academy which seem to combine the prison and the in succession to M. Royer Collard in 1847; hearse. The parallel would be imperfect, and if for his misfortune, it certainly was unless Downing Street, the Horse Guards, not to his discredit that he held the high and the Admiralty had been simultaneously invaded, and unless all the heads of departments, civil and military, with a large proportion of their subordinates, had been replaced by adventurers, or by persons whose main title to confidence under the new state of things was their failure or rejection under the old.

office of Minister of the Interior under Louis Philippe at the time when the present Emperor of the French effected his memorable landing at Boulogne. Liberal Conservative by opinion, he has constantly and consistently laboured to consolidate constitutional government in France; but he has resorted to no illegal or irregular method of enforcing or carrying out his views. Not so much as an irritating or ill-advised speech has been attributed to him. He was simply found at his post, along with all that was most venerable or estimable amongst Frenchmen, when the last representatives and defenders of French liberty were dispersed and outraged. Yet, without being ever charged with the semblance of a transgression against any known law, he is first hurried off to prison like a common malefactor, then exiled, and then excluded from public life as well as debarred from the unrestrained exercise of his faculties in other walks of mind.

Now, we should thereby have got rid of a good many of the abuses against which the administrative reformers have hitherto waged war in vain; and we should also have spared ourselves the trouble of hearing or reading many debates in which the speakers appear to have had no more exalted object in view than faction or self-display. The press, also, would not have enjoyed the proud privilege of libelling our army and discrediting our diplomacy, for the edification and encouragement of rival nations, which may speedily become our foes. Yet, for all that, most of us would not be sorry to have our old institutions, habits and liberties back again, even at the price of A nearly similar destiny has been imbeing obliged to endure occasionally an posed on almost all who for more than half indiscreet speech from a party leader out of a century have been wont to take the lead place, or a mischievous communication in administration or debate. Should this from a newspaper correspondent. Then state of things be prolonged, it can hardly why should we rejoice over the political and intellectual degradation of our neighbours across the Channel, and contend that they have been rightly served, because one out of a hundred of the chief sufferers may have abused their former freedom of writing or of speech?

Take the case of M. Charles de Remusat, the distinguished author of the work named

fail to pave the way for another revolutionary crisis, and it is a standing menace to every liberal government in Europe whilst it lasts. But the imperial despotism must be credited with one good result. It has certainly prevented some of the most eloquent writers and profoundest thinkers in France from giving up to party what was meant for mankind. We are probably in

debted to it for the completion of M. Thiers' | in a contrary direction. At least till very History; for the republication, in a corrected recently the newspaper press had been conand complete shape, of some of M. Guizot's stantly rising in influence and reputation, most valuable productions; and for a new and was rapidly gaining ground on the rest work on the never-failing theme of the first of our periodical literature, even in walks, French Revolution from the conscientious like literary criticism, where it might have and thoughtful pen of M. de Tocqueville. been expected that competition must prove M. de Montalembert's brilliant essays tell hopeless. This, however, is not the place their own story and explain their own origin; to speculate on the causes or consequences whilst we may be pardoned for suspecting of the change. Having simply noted it as that all M. de Remusat's fondness for the a curious and interesting fact, we return to more refined and belles-lettres part of political M. de Remusat's "Studies and Portraits," controversy, would hardly have induced the in which a series of familiar topics are inextent of research into the inmost recesses vested with an air of freshness, and rendered of English history and biography which is singularly attractive and instructive, by exhibited in the book before us, had the being seen from a foreign point of view and animating arena of public life been left open through the medium of a peculiarly trained to him and his friends. and abundantly stored mind.

The

The contents of these two volumes (1044 The first volume, after some preliminary closely printed octavo pages) first appeared reflections on the contrasted destinies of in the shape of articles in the Revue des Deux France and England in matters of governMondes; which at present enrols amongst ment is devoted to Bolingbroke, His Life its contributors, regular or occasional, a and Times. The second is occupied with large proportion of the writers of which Horace Walpole and Junius. Around the modern French literature has most reason main figures are grouped almost all the to be proud. The honour and advantage of statesmen and characters of note who figured first ushering M. de Montalembert's bro- on, or passed across, the stage of public life chures before the world are also enjoyed by in England between the English Revolution a magazine or review published twice a of 1688, and the French of 1789. To supmonth, Le Correspondant. The circum- pose that a Frenchman could suggest nothing stance is worth noting, because it indicates new on such a range of subjects simply be. a remarkable change in the journalism of the cause he is a Frenchman, would be a hasty two countries. During the first quarter of and illogical inference. Bolingbroke has the century, the English reviews were con- truly said, that history is read with different fessedly the best existing; and every effort eyes at different periods of life. A reader to rival them on the Continent confessedly of twenty carries off one set of impressions, failed. Thus the Revue Française, which a reader of thirty an additional set, a reader started under high auspices and was admir- of forty a still larger one, and so on. ably conducted, reached only a limited cir- suggestiveness of a narrative is, of course, culation; and the Revue des Deux Mondes increased tenfold by practical experience, had a long period of comparative neglect and the best interpreter of history is he who and indifference to live through. The daily has lived it, or played a part in analogous press of Paris long absorbed all the rising scenes. The bare lapse of years, also, may talent, and exercised a paramount influence supply fresh associations and original comand authority, which speedily became a mis- ments. Thus, every time the world is conchievous and capricious tyranny. Impa-vulsed or shaken by civil commotions in a tience at its excesses caused its far more great central community, the history of each than counterbalancing benefits to be over- preceding revolution is perused and repelooked for a period; and the enemies of free rused with renewed and unabated zeal, in the discussion gladly profited by the passing hope of discovering some satisfactory soluand shortsighted popular prejudice to sup- tion of the problem. The preceding labours press it altogether in what they rightly of Clarendon, Hume, Disraeli the elder, deemed its most formidable shape. Re- Godwin, Hallam, and Macaulay, have little, views, which are addressed to a different class if at all, weakened by anticipation the inof readers and cannot follow up their blows by a rapid and telling succession, are regarded with less jealousy, and still manage to express or insinuate unpalatable truths. They, therefore, have become, in France, the chief refuge and resource of both writers and readers who are on the look-out for novelty. In England, the tendency has been

terest taken in M. Guizot's Cromwell; nor, we think, with all due respect for the able work of Mr. Wingrove Cook, will it be the complaint of any candid critic, who may be induced to follow the tortuous career of Bolingbroke under M. de Remusat's guidance, that he has been wasting his time upon a beaten track or an exhausted field. Indeed,

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