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In the camera obscura but one set of objects, namely, those at some given distance, can form distinct images at one and the same time. In order to obtain a distinct view of objects at other distances, the lens must be moved farther, or brought nearer to the screen. The eye has the same properties; but this is no defect, for it is unnecessary that we should view more than a single object at a time. But it is absolutely essential that we should pass our vision from one object to another, with the rapidity of our own thoughts. The eye possesses this power of adaptation to different distances in the highest degree; between a distance of eight or nine inches and that of the fixed stars, the eye is capable of adapting itself to distant vision, and the more remote objects are only less known to us because the angle they subtend is lessened. Yet this extensive power is produced by means so trivial in comparison to the effect, that they are not yet admitted to be understood. We are of opinion, however, that Sir Edward Home solved the question a short time before his death. He discovered that the ligaments which sustain the crystaline lens in its place are muscular; the effort of their action would be to render the front of the eye more convex, and at the same time increase the length of its axis. These two changes would suffice to adapt the eye for the view of nearer objects ; a contrary action would prepare it for those more remote. It only remains that the antagonists of these muscles should be discovered, to make the explanation of the phenomenon complete. Another mode of accounting for the adaptation of the eye to vision at different distances is due to a distinguished countryman of our own, whose loss the scientific world has just been called upon to deplore. He ascribed a change in the figure and convexity of the eye to the united action of the four straight muscles which give it its vertical and horizontal motions; and here the explanation was complete, but it was necessary to conceive that muscles evidently intended as antagonists should concur in the operation, a case of which no other instance is known.
It is because the eye is best known to us, that it is a favourite object for the illustration of the argument of the natural theologian. The other organs of sense also manifest the utmost delicacy of arrangement, while their mechanism is so refined as in many cases to escape our highest powers of research into its object and action. Still, enough can be understood to show that where our knowledge is at fault, it is because that of the planner of these works exceeds our limited intelligence. Even in the eye, as in all senses, we are at once compelled to pause in our enquiries by a barrier which, it may safely be predicted,
* David Hosack, M. D., LL. D., F. R. S. &c. &c.
no human learning will ever be able to penetrate. We can trace the rays of light until they form an image on the retina, and show why the eye, considered merely as an optical instrument, far surpasses those constructed by human art; but we are unable to say how this picture becomes an object for the contemplation of the mind. Here the mysteries of nature become inscrutable, nor can we, while loaded with a material clog, be able to specify how, mind and matter mutually act upon each other.
We cannot better conclude our article than by extracting the eloquent passage with which our author closes his argument. .“ The pursuit of remote and often fanciful analogies has, by many of the continental physiologists, been carried to an unwarraptable and unreasonable length: for the scope which is given to the imagination in these seductive speculations, by leading us far away from the path of philosophical induction, tends rather to obstruct than to advance the progress of real knowledge. By confining our enquiries to more legitimate objects, we shall avoid the delusion into which one of the disciples of this transcendental school appears to have fallen, when he announces, with exultation, that the simple laws he has now discovered have explained the universe; nor shall we be disposed to lend a patient ear to the more presumptuous reveries of another system builder, who, by assuming that there exists in organized matter an inherent tendency to perfectibility, fancies that he can supersede the operations of divine agency,
“ Very different was the humble spirit of the great Newton, who, struck with the immensity of nature, compared our knowledge of her operations, into which he had himself penetrated so deeply, to that of a child gathering pebbles on the sea shore. Compared, indeed, with the magnitude of the universe, how narrow is the field of our perceptions, and how far distant from any approximation to a knowledge of the essence of matter, of the source of its powers, or even of the ultimate configuration of its parts! How remote from all human cognizance are the intimate properties of those imponderable agents, light, heat and electricity, which pervade space, and exercise so potent a control over all the bodies in nature! Doubtless there exist around us, influences of a still more subtle kind, which 'eye hath not seen, nor ear heard,' neither can it enter into the heart or imagination of man to conceive. How scanty is our knowledge of the mind; how incomprehensible is its connection with the body; how mysterious are its secret springs and inmost workings! What ineffable wonders would burst upon us, were we admitted to the perception of the spiritual world, now encompassed by clouds impervious to mortal vision !
“The great Author of our being, while he has been pleased to confer upon us the gift of reason, permits us to acquire by its exercise, a knowledge of some of the wondrous works of his creation, to interpret the characters of wisdom and goodness with which they are impressed, and to join our voices to the general chorus, which proclaims his Might, Majesty and Dominion. From the same gracious hand we also derive that unquenchable thirst of knowledge, which this fleeting life must ever leave unsatisfied; those endowments of the moral sense, with which the present condition of the world so ill accords; and that innate desire of perfection which our present frail condition is so inadequate to fulfil. But it is not given to man to penetrate into the counsels VOL. XIX.-NO. 38.
or fathom the designs of Omnipotence: for in directing his views into futurity, the feeble light of his reason is scattered and lost in the vast abyss. Although we plainly discern intention in every part of the creation, the grand object of the whole is placed far above the scope of our comprehension. It is impossible, however, to conceive that this enormous expenditure of power, this vast accumulation of contrivances and of machinery, and this profusion of existence arising from them, can thus, from age to age, be lavished without some ulterior end. Is man the favoured creature of nature's bounty, the paragon of animals, whose spirit holds communion with the celestial powers, formed but to perish with the wreck of his bodily frame? Are generations after generations of his race doomed to follow in endless succession, rolling darkly down the stream of time, and leaving no track in its pathless ocean? Are the operations of the Almighty power to end with the present scene? May we not discern, in the spiritual constitution of man, The traces of higher powers, to which those he now possesses are but preparatory ; some embryo faculties which raise us above this earthly habitation? Have we not in the imagination a power but little in harmony with the fetters of our bodily organs; and bringing within our view purer conditions of being, exempt from the illusions of our senses, and the infirmities of our nature, our elevation to which will eventually prove that all those unsated desires of knowledge, and all those ardent aspirations after moral good, were not implanted in us in vain ?
"Happily, there has been vouchsafed to us, from a higher source, a pure and heavenly light to guide our faltering steps, and animate our fainting spirit in this dark and dreary search; revealing those truths which it imports us most of all to know, giving to morality higher sanctions, elevating our hopes and our affections to nobler objects than belong to the earth, and inspiring more exalted themes of thanksgiving and of praise."
Art. IV.-1. The Report of and Testimony taken before the Joint
Committee of the Senate and House of Delegates, of Maryland, to which was referred the memorial of John B. Morris, Reverdy Johnson, and others, praying indemnity for losses sustained by reason of the riols in Baltimore, in the month of August, 1835.
Published by order of the General Assembly. Annapolis, 1836. 2. Testimony taken before the Joint Committee, fc. in behalf of
the Civil Authorities of Baltimore, &c. Annapolis, 1836. 3. An Act to indeninify Reverdy Johnson and others, &c. 4. An Act relating to Riots. Pamphlet Laws of Maryland, 1836.
The occasion of the passage of the acts of the Legislature of Maryland, which we have cited above, is doubtless fresh in the minds of our readers. The repose of the entire country was disturbed by the news of one of our finest cities being the prey of lawless rioters; that devastation in its most fearful shape (for
it is such, when the result of unbridled popular fury) was in progress upon noble private mansions and their costly furniture; and even fears were most justly entertained that murder, the savage rending of limb from limb, had closed the appalling and disgusting spectacle. The question was naturally put, where was the police, during this work of destruction ? where the able bodied townsmen of Baltimore? Are our laws so inefficient, our love of order and of justice so weak, that men could look upon havoc of this description without rushing to the rescue ? that no apprehensions of the supremacy of lawless passion and its possible outbreaking upon the property, nay, the persons, of each one in turn, could induce a union of the good against the bad ? Was it the case that riot and robbery could openly. exhibit their foul proportions and gather strength from impunity, without exciting the combined opposition of all good citizens? Our country, it was admitted, had not been a perfect stranger to such scenes, nor could the city in question, (and the retrospect brought a flush to the cheek, partly of anger and partly of shame,) claim a full exemption. But these were regarded as special though fearful dispensations of Providence, which, like earthquakes or volcanic eruptions, by their evidence of control over the general laws of nature, may be designed to awaken man to a knowledge of that God whom, in the smooth current of life, he is, too often, liable to forget.
One scourge had, but a short time before, passed through the land, and laid thousands low in the sleep of death. This fearful visitant had come upon the wings of the wind, and with noiseless step rendered its presence known only by its awful attendants, disease and dissolution. The recurrence of riot, in different quarters of our before comparatively quiet country, bursting suddenly forth, with no premonition and apparently without concert, led to the persuasion that an epidemic was traversing the body politic, the result of some mysterious action upon our citizens, which would pass off, like other providential visitations, and probably leave the state, cleared of noxious vapours, more healthy than before.
There were, however, upon mature reflection, circumstances attendant on the transactions, which induced more serious thoughts. Probable ground appeared for the suspicion, that there was something wanting in our system of police, we may say, indeed, of society, to restrain the outbreaks of her bad elements, and to call into more active exercise, her purer portions. It was not to be pretended that our land was without her evil elements, or that they needed no repression. There was too fearful proof to doubt their existence. It is aside from our present purpose, and therefore we shall not stop to enquire into the causes of their growth; but it became evident that
much was necessary to check their further progress, and guard against their consequent increase of strength. The apprehension was entertained, that popular passion being excited upon any of the thousand questions which are afloat in our community, each was to be resolved by an appeal to brute violence without waiting for the action of the constituted authorities, or in complete disregard of their decisions. That, in fact, Lynch law, which was supposed, theretofore, to be the peculiar evil of our western settlements, was about to plant its foot upon all parts of the Union.
These apprehensions were strengthened by the course of this riotous spirit. It did not commence its ravages in thinly populated or exposed situations; but, on the contrary, in the very heart of our oldest settlements, where the character of the population, for order and respect for the laws, was pre-eminent, and where, it was thought, the amplest opportunities and means were at hand for the suppression of disturbance. It originated not from any feelings connected with the exciting topic of slavery, or in a quarter where the solution of that momentous question is of the deepest practical importance, but was connected with (miscalled) religious sentiments, and was directed against helpless and unoffending females, and against an institution founded by one of the most numerous and the most ancient sect in the Christian world. The apathy with which, by many of the community in which it occurred, the transaction was regarded, was attributed, not without reason, to one of two causes ; either, (which we hope and believe not to have been the case,) that the laws had lost their hold upon the respect and attachment of the people, or that the defective organization of the police and of the moral strength of society allowed, in the first moments of surprise, full sway to the excesses of popular fury. Riot, robbery, and arson, revelled together, and murder was but accidentally absent.
Two farther instances followed in a still more central location, and in a city whose boast is propriety and quiet. The effects of both were in a great degree similar, though the exciting causes were different. In the one case the persons and the property of a distinct class of our population, of those who, from their difference of colour, and inferiority of rights and privileges, should be the special objects of protection, were marked out for destruction and outrage. Magnanimity, if no better feeling existed, should have been their safeguard ; but with a mob, who contemn religion and justice, the finer feelings of the heart can scarcely be supposed to have influence.
In the other case alluded to, the property of a citizen was destroyed during the excesses of popular excitement attendant upon an election. In a democratic republic like ours, where almost