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endeared to our imaginations by the nobleness of those objects for which he struggled with illustrious and self-devoting vehemence. We regard him with an awful sense of terror, which is almost reverential; and the few kindly words, contained in his letter to Morton, when embarking for Holland, are like flashes of paternal affection from the dark and clouded recesses of his spirit. We feel that he is still a man, and would fain persuade him to descend for a while from the tempestuous eminences of controversy and rebellion, to sit by our sides in the fair places of the earth, and be unto us as a brother.

Now, in both the cases we have cited, this sympathetic interest in the acts and feelings of the ideal personage, is founded in our common love of human nature, and in that spontaneous admiration with which we always look on virtue. So far as it relates to the vices or crimes of either character, it takes the form of regret, deplores the slave-like prostration of their eminent faculties beneath the ever-encroaching tyranny of evil habits and propensities; and laments their signal unhappiness, in being thus destined to make fetters for themselves, the iron whereof shall one day enter into their very souls. It is an interest in the individual, as a being like ourselves, equally capable, with us, of honourable emotion and of upright conduct. It proves both that these creatures of imagination are real semblances of our own intimate nature; and that the heart and mind of man can find no vital and abiding satisfaction, but in truth and rectitude and virtue. Compare the total effect of the character of Varney, with that produced upon the feelings of the reader by the Corsair or the Manfred of Lord Byron, and the force of our objection to the tendency of his Lordship's poetry will conspicuously appear.

Of the wondrous and a familiar knowledge of the human heart which illustrates the pages of these novels, we need say no more; that is a quality which every, the most cursory reader, at once perceives and confesses. It is felt that the actors and speakers of the tale are veritable human creatures; not mere unbreathing shadows, or fantastic and exaggerated shapings of the poet's pen. To borrow from an eloquent writer in the Quarterly, the fine application which he has made of Shakspeare's words: "Like the statue, in the Winter's Tale,' you would deem they breathed, and that those veins did verily bear blood: the fixture of their eyes has motion in it; an air comes from them, and the fine chisel has cut breath."

Let it be added, that they are, also, individual beings. The specific differences of mind are marked in them, as clearly as in actual life, and with the same delicate minuteness. Even when characters of the same class are brought before us, they are ever separated and distinguished from each other, by the bringing out of some smaller and finer shades of difference. Their very speech is characteristic and peculiar: we never mistake the expression and discourse of one for that of another. There are among them, those who deal in solemn common-places, and repeat the garbled observations of their superiors; but, these excepted, they have each an incommunicable style of thought, their feelings undergo personal modification, and are thus assimilated, harmonized, made their own, and coloured by the prevailing qualities of their nature. This is the great triumph of the poet's art, the glory of Homer and of Shakspeare. It is this which gives duration and eternal fame to the works of genius; which confers upon them the dignity, the beauty, the undecaying lustre of truth. Such works, thus written and conceived, demand for their authors the admiration and the reverence of mankind, in all climes, and in all ages. They shine as ethereal reflections of man's life, and present to the gaze of all generations an imperishable picture of their own spiritual being. Such are the writings of Sir Walter Scott, the man who was destined to revive, in the nineteenth century, the literary glories of the sixteenth; and to restore to the high and severe standards of their forefathers, the intellectual tastes of his countrymen :

Blessing be with them,-and immortal praise,
The poets, who on earth have made us heirs
Of TRUTH, and pure delight!

404

ON THE NATURE AND ADVANTAGES OF THE STUDY OF PHYSICS. Being the Substance of an Introductory Lecture, delivered to the Class of Natural Philosophy, at Guy's Hospital; by W. M. HIGGINS, Esq., F. G. S., &c. &c.

(Concluded from p. 310.);

We have considered, in the former part of this article, the manner in which the study of physical science should be conducted, and some of the advantages which accrue to the student himself, both from such studies in general, and from the investigation of some particular branches of physics. But it must be obvious to every one who makes a more extended estimate of the labour of these pursuits, as compared with the advantages they confer, that these are by no means the chief benefits which flow from them. The highest of these benefits are those which affect, not individuals, but all society, and that not by administering amusement, and rationally employing time, but by enhancing the comforts and remedying the evils of life. Let us, in elucidating these advantages, briefly observe, in one or two instances, the effects which the study of physics has produced on the most useful mechanical arts:

"Between the physical sciences, and the arts of life," says Sir John Herschel, in his incomparable Discourse on the Study of Natural Philosophy, &c., "there subsists a constant mutual interchange of good offices; and no considerable progress can be made in the one, without of necessity giving rise to corresponding steps in the other. On the one hand, every art is in some measure, and many entirely, dependent on those very powers and qualities of the material world which it is the object of physical inquiry to investigate and explain; and, accordingly, abundant examples might be cited of cases where the remarks of experienced artists, or even ordinary workmen, have led to the discovery of natural qualities, elements, or combinations, which have proved of the highest importance in physics."

Let us take naval architecture as an example :

The business of a naval architect is to construct a vessel, whether for war or for burden, of such a shape, that it may be carried in the best manner over the ocean, and at the same time offer the greatest convenience for the stowage of cargo and men. Could we pass in review the history of this art, we should not fail to observe that it has been entirely dependent on the progress of natural philosophy. There are two questions which immediately present themselves to our mind, as soon as we begin to think of shipbuilding: What constitutes the stability of floating bodies? and, What is the solid of smallest resistance? The science of hydrodynamics answers both these questions, and thus affords a datum from which the calculation, in all cases, may be made.

The stability of a floating body entirely depends upon the situation of its centre of gravity, in relation to its meta-centre; that is, the point at which the axes of the centre of gravity of the body, and of the fluid it displaces, intersect each other. When the centre of gravity is below the meta-centre, it is stable; when above, unstable, that is, will upset; and when the two points coincide, it is indifferent to motion.

ance.

This fact is evidently of the greatest importance to the naval architect; and intimately connected with it is that problem by which he is to discover the solid of smallest resistAll solid bodies experience resistance in moving though fluids, but that resistance differs according to their shape. A line-of-battle ship of seventy-four guns, would require twelve times the power to move her with a given velocity, broad-side first, as is required to move her in the usual manner. A broad surface, then, moving in a fluid, experiences a much greater resistance than a narrow one; but from this it might be imagined that a swift-sailing vessel ought to be built as narrow as possible, that she may cut her way through the waters. There is, however, a limit to the narrowness of a floating body, that it may be the solid of smallest resistance. A side wind would be liable to throw such a vessel on her leeward side, and thus endanger her safety. Science, however, determines this question, and assists the contriver in constructing a ship in such a way, that it may be adapted to its particular use, and yet be the solid of smallest resistance.

We might proceed to shew, that in the construction of the ship, so as to resist the strains to which she is subject, and in the form of her sails, the ship-builder is indebted to the natural philosopher. But if we might be permitted to take architecture as an example, it would be easy to shew that the science of construction is entirely dependent on the laws which are taught by physics. Unhappily, however, the undue attention which is in the present day paid to the decoration of buildings, has reduced the profession to an art; and all those works which require any considerable knowledge of natural philosophy, are now quietly relinquished by the majority of architects, and given to a branch of the profession called civil engineers.

It is scarcely necessary to advert to the absolute necessity of our sciences to this class of professional men. Not a step can be taken in the construction of bridges, rail-roads, or canals, without involving the principles of natural philosophy. It will only be necessary to offer one example. Let us suppose that it is required to build a flood-gate, every one knows that it will have to resist a pressure which will be exerted by the water, and a degree of strength must be given to it sufficient to do so. A person ignorant of the science of hydrodynamics would probably imagine that the force would be according to the bulk of water resting against it, and proceed to strengthen it accordingly. But this science teaches us that the amount of pressure upon the sides of a vessel is as the square of the depth of the fluid column, and therefore the pressure upon the flood-gate is according to the depth of water in contact with it, and that altogether independent of the quantity.

We might continue to multiply examples, by bringing them from the military and naval professions. Fortifications of all kinds, the theory of gunnery, and the art of guiding a vessel through the water, are all branches of natural philosophy; but we leave the consideration of these, to take a few examples from the medical profession. Every part of the human frame illustrates some principle in natural philosophy, and every instrument employed in surgery involves some mechanical or physical fact. In every country but our own, natural philosophy is considered a requisite branch of medical education, and most justly; for without an acquaintance with it, the mechanism of the human frame can never be understood: what are the limbs of animals, but levers? what the heart and blood-vessels, but an hydraulic apparatus? and who would be acquainted with the construction of the chest, the eye, and the ear, and yet remain ignorant of the sciences of pneumatics, optics, and acoustics. It is, therefore, most important to urge upon the medical profession, in particular, the study of natural philosophy, as an essential, and to them indispensable, department of knowledge. Indeed, motives of a peculiar force present themselves, inducing the students of medical science to these pursuits; for all the advantages which will result to the general student will be theirs, with the increased benefit of applying their knowledge to their professional occupations.

Nor is this their only motive: a review of the past advantages yielded to physical science by the medical profession, is highly calculated to stimulate the present gene. ration to similar efforts. Where will this, or any country, find names that will be brighter ornaments to the page of her history, than those of Wollaston and Young? Above all, the immense accessions made to the efficiency of medical science by the study of physics, is sufficient to compel the attention of all the members of that profession, no less from ambitious, than from philanthropic motives: and here we may best illustrate our position, by citing some passages on this subject from the admirable work of Sir John Herschel, to which allusion has already been made.

"It is to such observation," says he, speaking of the study of physical phenomena, "reflected upon, however, and matured into a rational and scientific form by a mind deeply imbued with the best principles of sound philosophy, that we owe the practice of vaccination; a practice which has effectually subdued, in every country where it has been introduced, one of the most frightful scourges of the human race, and in some extirpated it altogether. Happily for us, we know only by tradition the ravages of the small-pox, as it existed among us hardly more than a century

ago, and as it would in a few years infallibly exist again, were the barriers which this practice, and that of inoculation, oppose to its progress abandoned. Hardly inferior to this terrible scourge on land was, within the last seventy or eighty years, the scurvy at sea. The sufferings and destruction produced by this horrid disorder on board our ships, when, as a matter of course, it broke out after a few months' voyage, seem now almost incredible. Deaths to the amount of eight or ten a day in a moderate ship's company; bodies sewn up in hammocks, and washing about the decks, for want of strength and spirits on the part of the miserable survivors to cast them overboard; and every form of loathsome and excruciating misery of which the human frame is susceptible: such are the pictures which the narratives of nautical adventure in those days continually offer. At present the scurvy is almost completely eradicated in the navy, partly, no doubt, from increased and increasing attention to general cleanliness, comfort, and diet; but mainly from the constant use of a simple and palatable preventive, the acid of lemon, served out in daily rations. If the gratitude of mankind be allowed on all hands to be the just meed of the philosophic physician, to whose discernment in seizing, and perseverance in forcing it on public notice, we owe the great safeguard of infant life, it ought not to be denied to those whose skill and discrimination have thus strengthened the sinews of our most powerful arm, and obliterated one of the darkest features in the most glorious of all professions.

"One instance more, however, we will add, to illustrate the manner in which a most familiar effect, which seemed destined only to amuse children, or, at best, to furnish a philosophic toy, may become a safeguard of human life, and a remedy for a most serious and distressing evil. In needle manufactories, the workmen who point the needles are constantly exposed to excessively minute particles of steel which fly from the grindstones, and mix, though imperceptible to the eye, as the finest dust in the air, and are inhaled with their breath. The effect, though imperceptible on a short exposure, yet, being constantly repeated from day to day, produces a constitutional irritation dependent on the tonic properties of the steel, which is sure to terminate in pulmonary consumption; insomuch, that persons employed in this kind of work used scarcely ever to attain the age of forty years. In vain was it attempted to purify the air before its entry into the lungs, by gauzes or linen guards; the dust was too fine and penetrating to be obstructed by such coarse expedients, till some ingenious person bethought him of that wonderful power which every child who searches for its mother's needle with a magnet, or admires the motions and arrangement of a few steel filings on a sheet of paper held above it, sees in exercise. Masks of magnetised steel wire are now constructed, and adapted to the faces of the workmen. By these the air is not merely strained, but searched in its passage through them, and each obnoxious atom arrested and removed."

There would be no end to the enumeration of the public and more general advantages which have resulted from the study of natural philosophy. It has, like a Hercules, destroyed the monsters of superstition and priestcraft,—it has spread civilization through our land, increased the comforts of the poor, and the wealth of the rich,-it has given us the control of the ocean and the air,-given kindred to humanity, and united the ends of the earth.

It is quite impossible in the present day to estimate the amount of mischievous influence exercised by systems of philosophical imposture, on the ignorant of the early and middle ages. It is, doubtless, to be accounted for by the disproportion existing between the degree of their acquaintance with philosophy, and their ingenuity and taste in the arts, and consequent civilization. With all the susceptibility which refinement engenders, and yet with a total ignorance of religion and sound philosophy, and immersed in superstition and idolatry, it is easy to perceive that they must necessarily have been the helpless dupes of imposture. To what extent, however, they were misled and bewildered, it is difficult to ascertain. The secret recesses of the temple and the cave have not been thrown open, and exposed to our view. But this we do assuredly know, that philosophy has detected the cheat, and silenced and shamed the impostors.

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By her influence, associated with the more powerful energies of Christianity, the mind has been raised from its depth of degradation; and we now anticipate, in confident hope, the arrival of the day, when the whole world will acknowledge, and bow to their united influence.

But science has accomplished more than this, it has not only assisted in breaking the chains of superstition, but has opened that communication between men, in every part of the world, which, by allowing an interchange and communication of opinion, cannot fail to destroy prejudices and establish truth. We are not now the servants of the winds and the tides, but their masters; we have learned to combat nature with her own weapons, and in many instances have employed the very impediments that so long opposed our progress.

To the invention of the steam-engine we might refer, as one of the most surprising effects of the application of the human intellect to the study of physics. A vapour is the moving power; and though the least probable of all the attempts that have been made to obtain a power sufficient to counteract the impediments to motion existing in natural causes, is yet infinitely the most efficacious and controllable.

When rain falls upon the surface of the earth, it remains a short time, and disappears. You may not, perhaps, have thought to inquire why, but have satisfied yourselves with the idea that it passed through the soil. But there are some strata through which water cannot be filtered, they are impervious to its passage, and it can only pass over their surface as it would upon a basin of oil. Yet the rain that falls on the earth soon disappears. This arises from the action of the sun's rays, which, heating the surface of the earth, quietly carry away the redundant moisture as an invisible vapour.

The same process is going on from the surface of all the oceans, seas, and other masses of water, which cover so large a portion of the earth. Were it not for this, the amazing body of water which the Mediterranean sea, for example, receives of the many rivers and tributary streams which flow into it, would necessarily raise its level. But no such effect is produced,—there appears, on the other hand, to be a larger quantity evaporated from its surface, than is carried into its reservoir by these rivers and streams, for there is a constant current of water rushing into it from the Atlantic, through the streights of Gibraltar.

This is, perhaps, one of the conservatory principles of nature, by which the continuance of both vegetable and animal life is effected. But who, in the consideration of this phenomenon, or the analogous one of vapour rising from a boiling fluid, could ever imagine its application as a moving power. But the philosopher continues his investigations, ascertains its laws of action and of change, and at last invents the steamengine.

The application of the steam-engine is scarcely less remarkable than its invention. It has relieved man of part of that curse which rests upon him—" by the sweat of thy brow shalt thou eat bread." It saws his timbers, and forges his iron; it constructs his garments; it leaves him little more than the spectator of its marvellous operations. But its most remarkable application is that which constitutes a locomotive engine. It plows the mighty waters in its own strength, and virtually connects remote cities and nations, in spite of the distances and obstacles which nature herself has interposed.

The rail-way and the steam-boat give an importance to this and succeeding ages which cannot be too highly estimated. That despotism should be destroyed, and Christianity be established, a freedom of access between man and man is almost essential. That object has already been accomplished: the light of Christianity and science is spreading itself over the civilized world; and the time, we trust, is not far distant, when by their combined influence, all people of all tongues will be united in the bonds of a catholic philanthropy and a common faith.

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