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this science bear a remarkable similarity to those of Astronomy. It was then stationary; but has been again impelled by the energy of modern discoverers. That unobstructed vision takes place in straight lines, and that in cases of reflection the angles of incidence and reflection are equal, were laws so obvious, that it needed no long process of induction to establish them; a single step sufficed. The law of refraction was more recondite. The first step was, that refraction takes place towards the perpendicular; the second was a negative instance, that the angle of refraction was not proportional to the angle of incidence. When refraction became an element of Astronomy, more inquiry was directed into its laws. After many failures by other philosophers, it was at length discovered by Snell in 1621; and by the application of mathematics, the science of Formal Optics was soon made tolerably complete. Practical Optics, however, made but little progress, till the discovery of the composition of light by Newton; of which Bacon seems to have had some obscure notions, as appears by his comments on the "Instantiæ Solitaria" of crystals, prisms, and drops of water; which, when they exhibit colour, have nothing in common with the object seen but the colour itself. To Newton's experiments and hypotheses in Physical Optics few additions were made, till the discovery of the law of double refraction by Huyghens, which was afterwards verified by Young, Fresnel, Arago, and others. In this science, the phenomena of fringes, the colours of thin plates, and the beautiful and varied experiments connected with diffraction and polarization, may be viewed as "experimenta crucis" between the two conflicting hypotheses; and would lead us to give a decided preference to the undulatory theory; though we are far from following Mr. Whewell in the high ground which he adopts, in asserting its truth, and placing it on a level with the great law of Universal Gravitation. We may admit its superiority as a system, without being fully convinced of its truth as a theory. We insert the following passage, rather as showing the nature of the coincidences from which we generally infer an hypothesis to be true, than as being, in any peculiar sense, applicable to the undulatory theory of Optics. After stating that, on the corpuscular hypothesis, every additional class of phenomena demands a new supposition to be added to the theory, he says--

"In the undulatory theory, on the other hand, all tends to unity and simplicity. We explain reflection and refraction by undulations; when we come to thin plates, the requisite "fits," are already involved in our fundamental hypothesis, for they are the length of an undulation; the phenomena of diffraction also require such intervals; and the intervals thus required agree exactly with the others in magni

tude, so that no new property is needed. Polarization for a moment checks us; but not long, for the direction of our vibrations is hitherto arbitrary; we allow polarization to decide it. Having done this for the sake of polarization, we find that it also answers an entirely different purpose, that of giving the law of double refraction. Truth may give rise to such a coincidence; falsehood cannot. But the phenomena become more numerous, more various, more strange: no matter; the theory is equal to them all. It makes not a single new physical hypothesis ; but out of its original stock of principles it educes the counterpart of all that observation shows. It accounts for, explains, simplifies, the most entangled cases; corrects known laws and facts, predicts and discloses unknown ones; becomes the guide of its former teacher, observation; and, enlightened by mechanical conceptions, acquires an insight which pierces through shape and colour to force and cause."-Vol. II. p. 428-9.

Now, there can be no doubt that the undulatory theory of Optics is fully capable of explaining a great many of the most curious and remarkable phenomena connected with light; some of which, we may add, apparently do not admit of explanation on any other hypothesis which has hitherto been broached. Among them may be enumerated those to which Mr. Whewell refers, the colours of thin plates and striated surfaces, which, in 1801, led Dr. Young to the re-discovery of the theory, which had formerly been adopted by Huyghens, but since fallen into oblivion ;-the fringes of colours accompanying shadows, explained in a simple and beautiful manner by the principle of the "Interference of Undulations ;"-the phenomenon of double refraction, which is accounted for by supposing the elasticity of the luminiferous ether to be different in different directions; the law of this difference being expressed with great simplicity by a mathematical artifice, showing that the undulations are changed from spherical to spheroidal ;polarization explained on this theory by supposing transverse vibrations, a doctrine which possesses a striking correspondence with that of double refraction;-depolarization explained by combining with the last two the principle of interferences;-and lastly, the facts accounted for by the hypothesis of circular polarization, which was discovered by Fresnel, by interpreting, on mathematical principles, certain results algebraically impossible; and which has since been generalized by Professor Airy into the theory of elliptical polarization. We also admit that, in general, the actual results obtained from the application of these doctrines coincide, with tolerable exactness, with the phenomena shown by experiment; and this circumstance leads us to suppose, that whatever may ultimately prove to be the true physical theory of light, it will require the investigation of mathematical formulæ, closely resembling those which have been found necessary to carry out the undulatory

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theory. But yet, when we consider, that the theory has not accounted for, and does not appear at all calculated to account for, the absorption of light, and the colours of bodies in general; and that it has not explained, what it certainly ought to have done, reflection from crystallized surfaces and the prismatic dispersion of colour, though, in the latter instance, aided by the "additional mechanism" of finite intervals between the particles of ether; and, in short that out of the seven leading phenomena of light, (reflection, refraction, double refraction, interferences, polarization, dispersion, and absorption,) the first two may be explained without the theory, and the last two cannot be explained by it; we think that we are justified in stating, that the undulatory theory of Optics is not entitled to take its stand on the same level as that of universal gravitation; and that, whatever may be its merits as a mathematical hypothesis, (and great they undoubtedly are,) it will be much to the advantage of science, that future experiments should be directed, rather to discover another foundation for a physical theory, than to pile up materials upon the present.

We are anxious not to appear to underrate the magnitude, or depreciate the value, of the labours of the great men who conceived and carried out this truly wonderful hypothesis; and many of whom are still engaged in attempting to verify and complete it, and to remove those difficulties which are admitted by its warmest supporters. They have collected, with incredible perseverance, a large body of facts, not inferior in interest and importance to the results of the labours of Kepler, and at first sight, so various and irreconcilable, as to deter ordinary observers from attempting to unite them in any general law; and they have also invented a mathematical theory, (for such we must consider it), capable of accounting for them with singular felicity and accuracy, and possessing a remarkable correspondence with the fundamental principles of other kindred sciences; but the bold and imposing nature of the theory only renders it a matter of greater importance to the interests of science, that philosophers should not imagine, that they have arrived at the epoch of mathematical deduction, when perhaps they have not yet sufficiently established, by inductive reasoning, the principles upon which they proceed; that they should not (to adopt a parallel similar to Mr. Whewell's *) conceive themselves as standing in the position of Newton or Laplace, when, possibly, they may not as yet have reached the Epoch of Copernicus.

* Hist. vol. II. p. 462.

The general laws of Galvanic and Electrical Attraction belong to Bacon's Instantiæ Divortii; being separated from Newton's law of Gravitation. The progress of these several theories since the time of their conception,-the science of Chemistry generally,-might each be. made the subject of a separate essay; but, having dwelt so long on the Mechanical and Optical sciences, it is not possible, within the limits of the present notice, to touch even in the slightest manner, upon their distinct steps of advancement. They form continuous examples of inductive reasoning, scarcely inferior in point of interest to the progress of Mechanics and Astronomy; and exhibit some of the most striking enblems of the dominion of man over the realms of nature.

ART. VI.-FALSE CRITICISMS—JULIET AND PORTIA.

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"We said Bassanio was a fortune-hunter: so he is."

THERE are occasions when truth itself is untrue. It is not the highest range of truth. It is the literal truth of fact, but not the real truth of nature. This we hold to be the case, if, where any character has been untruly and unworthily estimated by a critic, something more than mere display of the untruth is not attempted by the respondent,— if he do not also give vent to his indignation at the unworthiness.With this preface, we proceed.

If there is one unlucky topic, rather than another, which has been drowned in ink- -or ought to have been, had not the subject as many lives as the constitution-the Shakspere characters have surely been long enough in the agonies of strangulation. Under every variety of classification, everything possible has been said of every one of them. The male characters, the female characters, the first-rate characters, the second-rate characters, the minor characters, the unfinished characters not to mention chapters without end, specially devoted to the idiosyncracies of Launcelot Gobbo, esquire, (witness for the esquire his almost "angry parle" with his revered parent) have each and all been the untired-would we could say untiring-theme of lackadaisical ladies, distraught doctors, and "puny whipsters" of every degree.

We trust the deliberate candour of this exordium will relieve our readers from any alarm they may have felt, lest we too should be following a multitude to do evil. We have no such purpose. The gold has already been beaten out so fine, that we would not "deal" upon it again for the world. Besides that, it has somehow got overlaid with a thick coating of surely not dirt; a hammer was never our weapon; we never could thump, or strike a knock-down blow. It was more congenial to our natural quickness, to run through our victim with the rapier.

We visit this chaos of contending creeds and clashing opinions of the unnumbered admirers of Shakspere's sketches,-or their own, unstunned by the hubbub which would long since have deafened us, had not our presiding genius, mercurialium custos virorum, made our ears impervious to the uproar. Yet, as far as anything could be dimly seen in these dark regions of criticism, as far as we could discern any fixed appearance where all was restless, where each individual creation of the poet's genius was only cramped into one attitude by one critic to be shoved out of it the next moment by another, two sights roused our indignation, and determined us to subvert the empire, to lay waste the territory, of the critics. We saw there Juliet and Portia-Romeo's Juliet, and Bassanio's Portia. Each petty wrong was the portion of the one; gauds and finery were heaped upon the other. We saw Juliet sitting disconsolate in the abode of Laodamia, both lovers "not wisely"

-so said the critics" but too well." We saw her rival followed by troops of friends, hanging on her honied speeches, and declaring her to be

"The wisest, virtuousest, discreetest, best,❞—

in short, another Eve.

Now what are the facts? The one is all talk, the other all action. The one does everything for love, the other a little for herself. The one makes Romeo the god of her idolatry, the other makes Bassanio the puppet of her joke. Portia makes fine speeches, Juliet does fine actions. Juliet foregoes all for a truly gallant gentleman, Portia flings away herself and her ducats upon a sentimental fortune-hunter. Juliet received her husband into her chamber at night secretly, for the love she bore him. Portia directly after her marriage tells her's that she has exposed herself in man's clothes in the face of day, in his presence, for a good jest. In fine, Juliet said truly of marriage, "It is an honour that I dream not of," and Portia dreamt of it every night in the week." But we will go fairly through the plays. And we will confess at the outset, that there appears to us something so nobly rash, such a generous

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