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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, re. who 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 Had Mr. Glaisher been acquainted with easily, but as the eyes become more longMr. Salom's visometer, he would have given sighted with age, new and deeper glasses it his highest recommendation. An inequa- should be substituted. The eye is an organ lity in the focal length of the eyes is a much of too delicate a structure to be rudely used, more common affection than is generally and it cannot with impunity be exposed every supposed; and therefore the first duty of an day to a constant strain, striving to see what optician is to determine whether or not such is beyond its power, to pry into what is too an inequality in the eyes exists, and then to minute, or to decipher what is indistinct or ascertain the focal length of the lenses re- confused. There are many objects to which quired to equalize them. In a case of this our attention is called, when our spectacles kind, which came under our notice, the in- fail to give us their usual aid. In looking at equality was so great as to produce double vi- maps, for example, a reading-glass is absosion of persons in the street,--an effect which lutely necessary, and if it is used along with was doubtless owing to an effort of the eyes our spectacles, it will be found to give a peto obtain distinct vision of one of the per- culiar relief to the eyes, and will be often sons by getting rid of the other. We sent used in reading books in small type, for this person to Mr. Salom, who constructed which our usual spectacles have not sufficient spectacles with lenses of different focal power. These reading.glasses must, of lengths, so as to make the images in each course, have a greater diameter than two eye equal, and we have learnt that the du- and a half inches, and though each eye plication of objects ceased to take place. 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 which well indicates the knowledge possessage, a third pair of spectacles for viewing ed by even the better order of spectaclevery distant objects, and having very long sellers." This denunciation of “ Binocular” focal lengths, will be found particularly reading-glasses is to us quite incomprehensiuseful.

ble. They neither double objects, nor ren

der them confused, and we found them, when * Lectures on the Results of the Great Exhibition of

used along with spectacles, one of the most 1851, delivered before the Society of Arts, at the suggestion of Prince Albert. P. 360. London: 1852.

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

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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 spec- fold into an eye-glass, will be found a very tacles with lenses much more convex than convenient form for out-of-door use, as the those we require for reading, or two pair eye-glass, having twice the magnifying power may be used together. This mode of see. of the spectacles, may be advantageously ing very minute objects is particularly con- resorted to as a microscope of small power. venient when we require the use of our hands, When we consider the varying intensities and we would counsel the artist, as well as of light to which the eye is exposed, from 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 excessive light, and they are decidedly the work with which we are acquainted, and Mr. best of all coloured glasses, as they absorb Smee does not not seem to be aware of their the extreme violet and blue rays, and transexistence. We have now before us a lens mit the red, thus producing a shorter specexecuted for us, above forty years ago, by trum, and consequently à more distinct Mr. Peter Hill, optician in Edinburgh, and image on the retina. Fashion, however, we have seen one or two very well made by always the victim of ignorance, has introthe London artists.

duced 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 spectacles made and used by the inhabitants should have spectacles of various numbers, of Greenland, for preventing snow blindness. from those which they require to see their They are made of wood, and have no lenses. food, or their friends on the opposite side The light is transmitted to each eye through of the table, to those which they require to a slit about 2 inches long, and the 50th of avoid danger in the street, to see pictures an inch wide, and becoming wider at the ends in a gallery, or to enjoy the near or the dis- next the nose. Immediately behind each tant landscape.

slit, the piece of wood is formed into a small In the preceding observations we have hollow box, the side of which press gently taken no notice of eye-glasses, which are upon the temples, the eyebrows, and the seldom used, excepting by those who are cheeks, so as to exclude all light whatever, ashamed to employ spectacles. To look at excepting that which passes through the slits.

The great length of the slits is necessary to * Art OPTICS, Encycl. Brit., vol. xvi. p. 388. give the vision of objects to the extreme

right and left, when the eyeball is turned most precious of his blessings, and he will as far as it can be turned in these directions. have saved himself many hours of anxieiy,

But while it is necessary to diminish light and many years of suffering, if he is so forof high intensity, it is often as necessary to tunate as to spend the last decade of his life increase it. In parts of the earth where with his eyes bright, and his vision unimthe nights are long, and the sun's light with paired. In the ordinary diseases to which drawn even during the day, so that the the eye, like the other parts of his body is inhabitants require the aid of artificial light, subject, we may safely confide in the skill it is of importance to discover the resources of the experienced physician; but in the with which science can supply us. We diseases to which it is liable as an optical have long been of opinion that certain rays instrument, where optical science can alone act more powerfully upon the retina than direct us, we regret that professional assisothers, though their illuminating power be tance is difficult to be found. Guided by less. We have known cases in which the practice, the skilful oculist may dexterously eye, in certain states, is more or less blind extract the crystalline lens, or make an arto particular colours, not only in persons tificial pupil; but all the refinements of who are colour-blind, but in persons of or- optical science are requisite in the practidinary sight when the eye has been pre- tioner to whom we commit the care of our viously under the influence of light. We sight; and we trust the time is not distant have, therefore, from observation as well as when men will be expressly educated for from theory, been led to believe that the this branch of the healing art, and will exyellow rays have a more powerful action on haust in their practice the rich resources the retina than even white light, and, with which science can supply them. 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 artifi- Art. V. – L' Angleterre au Dix-huitième cial illumination can be obtained, the en- Siècle ; Etudes et Portraits pour servir à largement of the pupil, either by waiting in l'Histoire du Gouvernement Anglais depuis the dark till it expands sufficiently, or by la fin du Regne de Guillaume III. Par the application of belladonna, might enable M. CHARLES REMUSAT, de l'Académie us to find it, or by means of a lens we Française. Deux Volumes. Paris, 1840. might condense the faint light to a certain degree, for it is light more than distinct The majority of Englishmen who tacitly vision that is required to find anything in approve or carelessly defend the existing feeble light.

regime in France, commonly lay out of the In proportion to the assistance which we account one of its most dangerous and (we derive from spectacles, is the misery which fear) utterly irremediable results or conwe experience in losing or mislaying them, comitants -- the exclusion from the public under circumstances where they cannot be service of almost every trained politician, replaced. On such occasions we are for who, prior to December 1851, had given certain purposes blind, and there are few decided proofs of talent and integrity. To persons advanced in life who have not fre- carry out the coup d'état, it was (or was quently experienced this misfortune. In deemed) necessary to place under temporary such a dilemma we may achieve a temporary restraint, with peculiar circumstances of perrecovery of our sight by looking, or even sonal insult and degradation, between two reading, through a pin-hole held close to and three hundred of the most eminent the eye, by making an extempore lens with members of the Assembly which had just a drop of varnish, or wine, or even water, been dissolved by violence. Three-fourths laid upon a clean piece of glass, or by of these were not even accused or suspected placing it on the hollow side of our watch- of intrigues or conspiracies. Their offence glass; or what is best of all, by crossing at was their moral weight, their acknowledged right angles two cylindrical bottles filled respectability, and their apprehended influwith water, and looking through the portion ence over the popular mind, should they be that is crossed.

left free to vindicate the outraged dignity of If the reader has followed us intelligently the constitution. For merely protesting throughout these pages, and has any faith in against the illegal force put upon the reprethe results and deductions of science, he will sentative body to which they belonged, or not fail to watch over his eyesight as the 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 - à 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 office of Minister of the Interior under Louis invaded, and unless all the heads of depart- Philippe at the time when the present ments, civil and military, with a large pro- Emperor of the French effected his memorportion of their subordinates, had been able landing at Boulogne. Liberal Conserreplaced by adventurers, or by persons vative by opinion, he has constantly and whose main title to confidence under the consistently laboured to consolidate constinew state of things was their failure or tutional government in France; but he has rejection under the old.

resorted to no illegal or irregular method of Now, we should thereby have got rid of enforcing or carrying out his views. Not a good many of the abuses against which the so much as an irritating or ill-advised speech administrative reformers have hitherto has been attributed to him. He was simply waged war in vain; and we should also found at his post, along with all that was have spared ourselves the trouble of hearing most venerable or estimable amongst or reading many debates in which the Frenchmen, when the last representatives speakers appear to have had no more exalted and defenders of French liberty were disobject in view than faction or self-display. persed and outraged. Yet, without being The press, also, would not have enjoyed the ever charged with the semblance of a transproud privilege of libelling our army and gression against any known law, he is first discrediting our diplomacy, for the edifica- hurried off to prison like a common maletion and encouragement of rival nations, factor, then exiled, and then excluded from which may speedily become our foes. Yet, public life as well as debarred from the for all that, most of us would not be sorry unrestrained exercise of his faculties in other to have our old institutions, habits and walks of mind. 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 å 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 fail to pave the way for another revolutionintellectual degradation of our neighbours ary crisis, and it is a standing menace to across the Channel, and contend that they every liberal government in Europe whilst have been rightly served, because one out it lasts. But the imperial despotism must of a hundred of the chief sufferers may have be credited with one good result. It has abused their former freedom of writing or certainly prevented some of the most eloof speech?

quent writers and profoundest thinkers in Take the case of M. Charles de Remusat, France from giving up to party what was the distinguished author of the work named' meant for mankind. We are probably in

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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 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. The ably conducted, reached only a limited cir- suggestiveness of a narrative is, of course, culation ;, and the Revue des Deux Mondes incrcased 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 rightsy of Clarendon, Hume, Disraeli the elder, deemed its most formidable shape. Re Godwin, Ilallam, 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 terest taken in M. Guizot's Cromwell; nor, by a rapid and telling succession, are re- we think, with all due respect for the able garded with less jealousy, and still manage work of Mr. Wingrove Cook, will it be the to express or insinuate unpalatable truths. complaint of any candid critic, who may be They, therefore, have become, in France, the induced to follow the tortuous chief refuge and resource of both writers Bolingbroke under M. de Remusat's guidand readers who are on the look-out for ance, that he has been wasting his time upon novelty. In England, the tendency has been la beaten track or an exhausted field. Indeed,

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