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SCIENCE AND ART.

FIFTEENTH MEETING OF THE BRITISH | which renders it almost a matter of certainty that ASSOCIATION FOR THE ADVANCE- an increase of optical power would show them MENT OF SCIENCE.

to be similarly composed. A not unnatural or unfair induction would therefore seem to be,

AT CAMBRIDGE.—SIR J. HERSCHELL PRESIDING. that those which resist such resolution do so

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In order to give this Report, we omit Bibliographical Notices, and Select List of Recent Publications -ED.

LORD ROSSE'S TELESCOPE.-Sir J. Herschell, in his introductory address, thus speaks:

"The last year must ever be considered an epoch in Astronomy, from its having witnessed the successful completion of the Earl of Rosse's six-feet reflector-an achievement of such magnitude, both in itself as a means of discovery, and in respect of the difficulties to be surmounted in its construction, (difficulties which perhaps few persons here present are better able from experience to appreciate than myself,) that I want words to express my admiration of it. I have not myself been so fortunate as to have witnessed its performance, but from what its noble constructor has himself informed me of its effects on one particular nebula, with whose appearance in powerful telescopes I am familiar, I am prepared for any statenient which may be made of its optical capacity. What may be the effect of so enormous a power in adding to our knowledge of our own immediate neighbors in the universe, it is of course impossible to conjecture; but for my own part I cannot help contemplating, as one of the grand fields open for discovery with such an instrument, those marvellous and mysterious bodies, or systems of bodies, the Nebula. By far the major part, probably, at least nine-tenths of the nebulous contents of the heavens consist of nebula of spherical or elliptical forms presenting every variety of elongation and central condensation. Of these a great number have been resolved into distinct stars, and a vast multitude more have been found to present that mottled appearance

only in consequence of the smallness and closeness of the stars of which they consist; that, in short, they are only optically and not physically nebulous. There is, however, one circumstance which deserves especial remark, and which, now that my own observation has extended to the nebula of both hemispheres, I feel able to announce with confidence as a general law, viz., that the character of easy resolvability into separate and distinct stars, is almost entirely confined to nebula deviating but little from the spherical form; while, on the other hand, very elliptic nebulæ, even large and bright ones, offer much greater difficulty in this respect. The cause of this difference must, of course, be conjectural, but, I believe, it is not possible for any one to review seriatim the nebulous contents of the heavens without being satisfied of its reality as a physical character. Possibly the limits of the conditions of dynamical stability in a spherical cluster may be compatible with less numerous and comparatively larger individual constituents than in an elliptic one. Be that as it may, though there is no doubt a great number of elliptic nebula in which stars have not yet been noticed, yet there are so many in which they have, and the gradation is so insensible from the most perfectly spherical to the most elongated elliptic form, that the force of the general induction is hardly weakened by this peculiarity; and for my own part I should have little hesitation in admitting all nebulae of this class to be, in fact, congeries of stars. And this seems to have been my father's opinion of their constitution, with the exception of certain very peculiar looking objects, respecting whose nature all opinion must for the present be suspended. Now, among all the wonders which the heavens present to our contemplation, there is none more astonishing than such

On both these subjects works of first-rate importance have of late illustrated the scientific literature of this country. On the philosophy of science, we have witnessed the production, by the pen of a most distinguished member of this university, of a work so comprehensive in its view, so vivid in its illustrations, and so right-minded in its leading directions, that it seems to me impossible for any man of science, be his particular department of inquiry what it may, to rise from its perusal without feeling himself strengthened and invigorated for his own special pursuit, and placed in a more favorable position for discovery in it than before, as well as more competent to estimate the true philosophical value and import of any new views which may open to him in its prosecution. From the peculiar and à priori point of view in which the distinguished author of the work in question has thought proper to place himself before his subject, many may dissent; and I own myself to be of the number;-but from this point of view it is perfectly possible to depart without losing sight of the massive reality of that subject itself; on the contrary, that reality will be all the better seen and understood, and its magnitude felt, when viewed from opposite sides, and under the influence of every accident of light and shadow which peculiar habits of thought may throw over it.

elose compacted families or communities of stars, Į lectual faculties. If we are ever to hope that sciforming systems either insulated from all others, ence will extend its range into the domain of social or in binary connection, as double clusters whose conduct, and model the course of human actions confines intermix, and consisting of individual on that thoughtful and effective adaptation of stars nearly equal in apparent magnitude, and means to their end, which is its fundamental princrowded together in such multitudes as to defy ciple in all its applications (the means being here all attempts to count or even to estimate their num- the total devotion of our moral and intellectual bers. What are these mysterious families? Un- powers-the end, our own happiness and that of der what dynamical conditions do they subsist? all around us)-if such be the far hopes and long Is it conceivable that they can exist at all, and protracted aspirations of science, its philosophy endure under the Newtonian law of gravitation and its logic assume a paramount importance, in without perpetual collisions? And, if so, what a proportion to the practical danger of erroneous problem of unimaginable complexity is presented conceptions in the one, and fallacious tests of the by such a system, if we should attempt to dive into validity of reasoning in the other. its perturbations and its conditions of stability by the feeble aid of our analysis. The existence of a luminous matter, not congregated into massive bodies in the nature of stars, but disseminated through vast regions of space in a vaporous or cloud-like state, undergoing, or awaiting the slow process of aggregation into masses by the power of gravitation, was originally suggested to the late Sir W. Herschell in his reviews of the nebulæ, by those extraordinary objects which his researches disclosed, which exhibit no regularity of outline, no systematic gradation of brightness, but of which the wisps and curls of a cirrhus cloud afford a not inapt description. The wildest imagination can conceive nothing more capricious than their forms, which in many instances seem totally devoid of plan, as much so as real clouds-in others offer traces of a regularity hardly less uncouth and characteristic, and which in some cases seems to indicate a cellular, in others a sheeted structure, complicated in folds as if agitated by internal winds. Should the powers of an instrument such as Lord Rosse's succeed in resolving these also into stars, and, moreover, in demonstrating the starry nature of the regular elliptic nebula, which have hitherto resisted such decomposition, the idea of a nebulous matter, in the nature of a shining fluid, or condensible gas, must, of course, cease to rest on any support derived from actual observation in the sidereal heavens, whatever countenance it may Accordingly, in the other work to which I have still receive in the minds of cosmogonists from the made allusion, and which, under the title of a tails and atmospheres of comets, and the zodiacal "System of Logic," has for its object to give "a light in our own system. But though all idea of connected view of the principles of evidence and the its being ever given to mortal eye, to view aught methods of scientific investigation"-its acute and that can be regarded as an outstanding portion of in many respects profound author-taking up an primæval chaos, be dissipated, it will by no means almost diametric ally opposite station, and looking have been even then demonstrated that among to experience as the ultimate foundation of all those stars, so confusedly scattered, no aggregat knowledge-at least, of all scientific knowledgeing powers are in action, tending to draw them in its simplest axioms as well as in its most remote into groups and insulate them from neighboring results-has presented us with a view of the ingroups; and, speaking from my own impressions, ductive philosophy, very different indeed in its I should say that, in the structure of the Magel- general aspect-but in which, when carefully exlanic clouds, it is really difficult not to believe we amined, most essential features may be recognized see distinct evidences of the exercise of such a as identical, while some are brought out with a power. This part of my father's general views salience and effect which could not be attained of the construction of the heavens, therefore, being from the contrary point of sight. It cannot be exentirely distinct from what has of late been called pected that I should enter into any analysis or "the nebulous hypothesis," will still subsist as a comparison of these remarkable works-but it matter of rational and philosophical speculation-seemed to me impossible to avoid pointedly menand perhaps all the better for being separated from

the other.

"A great deal of attention has been lately, and I think very wisely, drawn to the philosophy of science and to the principles of logic, as founded, not on arbitrary and pedantic forms, but on a careful inductive inquiry into the grounds of human belief, and the nature and extent of man's intel

tioning them on this occasion, because they certainly, taken together, leave the philosophy of science, and indeed the principles of all general reasoning, in a very different state from that in which they found them. Their influence, indeed, and that of some other works of prior date, in which the same general subjects have been more lightly touched upon, has already begun to be felt and responded to from a quarter where, perhaps,

any sympathy in this respect might hardly have any conceivable system of Boscovichian alternabeen looked for. The philosophical mind of Ger- tions,) will be deemed untenable. Already we many has begun, at length, effectually to awaken have introduced the idea of heat-atmospheres about from the dreamy trance in which it had been held particles to vary their repulsive forces according for the last half century, and in which the jargon to definite laws. But surely this can only be reof the Absolutists and Ontologists had been re-garded as one of those provisional and temporary ceived as oracular. An "anti-speculative philos- conceptions which, though it may be useful as ophy" has arisen and found supporters-rejected, helping us to laws, and as suggesting experiments, indeed, by the Ontologists, but yearly gaining we must be prepared to resign if ever such ideas, ground in the general mind. It is something so for instance, as radiant stimulus or conducted innew for an English and a German philosopher to fluence should lose their present vagueness, and agree in their estimate either of the proper objects come to receive some distinct scientific interpreof speculation or of the proper mode of pursuing tation. It is one thing, however, to suggest that them, that we greet, not without some degree of our present language and conceptions should be astonishment, the appearance of works like the held as provisional-another to recommend a Logic and the new Psychology of Beneke, in general unsettling of all received ideas. Whatwhich this false and delusive philosophy is entirely ever innovations of this kind may arise, they can thrown aside, and appeal at once to the nature only be introduced slowly, and on a full sense of of things as we find them, and to the laws of our their necessity; for the limited faculties of our intellectual and moral nature, as our own con- nature will bear but little of this sort at a time sciousness and the history of mankind reveal them without a kind of intoxication, which precludes to us.* all rectilinear progress-or, rather, all progress whatever, except in a direction which terminates in the wildest vagaries of mysticism and clairvoyance.

Which

Meanwhile, the fact is every year becoming more broadly manifest, by the successful application of scientific principles to subjects which had hitherto been only empirically treated, (of which But, without going into any subtleties, I may agriculture may be taken as perhaps the most con- be allowed to suggest that it is at least high time spicuous instance,) that the great work of Bacon that Philosophers, both physical and others, should was not the completion, but, as he himself foresaw come to some nearer agreement than appears to and foretold, only the commencement of his own prevail as to the meaning they intend to convey philosophy; and that we are even yet only at the in speaking of causes and causation. On the one threshold of that palace of truth which succeeding hand we are told that the grand object of physicgenerations will range over as their own-a world al inquiry is to explain the phenomena of nature, of scientific inquiry, in which not matter only and by referring them to their causes; on the other, its properties, but the far more rich and complex that the inquiry into causes is altogether vain and relations of life and thought, of passion and motive, futile, and that science has no concern, but with interest and actions, will come to be regarded as the discovery of laws. Which of these is the its legitimate objects. Nor let us fear that in so truth? Or are both views of the matter true on regarding them we run the smallest danger of col- a different interpretation of the terms? lision with any of those great principles which we ever view we may take, or whichever interpretaregard, and rightly regard, as sacred from ques- tion adopt, there is one thing certain the extreme tion. A faithful and undoubting spirit carried inconvenience of such a state of language. This into the inquiry, will secure us from such dangers, can only be reformed by a careful analysis of this and guide us, like an instinct, in our paths through widest of all human generalizations, disentangthat vast and enlarged region, which intervenes be-ling from one another the innumerable shades of tween those ultimate principles and their extreme practical applications. It is only by working our way upwards towards those principles as well as downwards from them, that we can ever hope to penetrate such intricacies, and thread their maze; and it would be worse then folly-it would be treason against all our highest feelings-to doubt that to those who spread themselves over these opposite lines, each moving in his own direction, a thousand points of meeting and mutual and joyful recognition will occur.

Until

meaning which have got confounded together in
its progress, and establishing among them a ra-
tional classification and nomenclature.
this is done we cannot be sure that by the rela-
tion of cause and effect one and the same kind of
relation is understood. Indeed, using the words
as we do, we are quite sure that the contrary is
often the case; and so long as uncertainty in this
respect is suffered to prevail, so long will this un-
seemly contradiction subsist, and not only preju-
dice the cause of science in the eyes of mankind,
but create disunion of feeling, and even give rise
to accusations and recriminations on the score of
principle among its cultivators.

But if science be really destined to expand its scope, and embrace objects beyond the range of merely material relation, it must not altogether and obstinately refuse, even within the limits of The evil I complain of becomes yet more griev such relations, to admit conceptions which at first ous when the idea of law is brought so prominentsight may seem to trench upon the immaterial, ly forward as not merely to throw into the backsuch as we have been accustomed to regard it. ground that of cause, but almost to thrust it out of The time seems to be approaching when a merely view altogether; and if not to assume something mechanical view of nature will become impossible approaching to the character of direct agency, at -when the notion of accounting for all the phe- least to place itself in the position of a substitute nomena of nature, and even of mere physics, by for what mankind in general understand by expla simple attractions and repulsions fixedly and un-nation: as when we are told, for example, that changeably inherent in material centres, (granting

mirable view of the state of metaphysical and logical philoso* Vide Beneke, Neue Psychologie, s. 300 et seq., for an adphy in England.

the successive appearance of races of organized beings on earth, and their disappearance, to give result of some certain law of development, in virplace to others, which geology teaches us-is a

tue of which an unbroken chain of gradually exalted organization from the crystal to the globule, and thence, through the successive stages of the polypus, the mollusc, the insect, the fish, the reptile, the bird, and the beast, up to the monkey and the man (nay, for ought we know, even to the angel,) has been (or remains to be) evolved. Surely, when we hear such a theory, the natural, human craving after causes, capable | in some conceivable way of giving rise to such changes and transformations of organ and intellect-causes why the development at different parts of its progress should divaricate into different lines-causes, at all events, intermediate between the steps of the development-becomes importunate. And when nothing is offered to satisfy this craving, but loose and vague references to favorable circumstances of climate, food, and general situation, which no experience has ever shown to convert one species into another; who is there that does not at once perceive that such a theory is in no respect more explanatory, than that would be which simply asserted a miraculous intervention, at every successive step of that unknown series of events, by which the earth has been alternately peopled and dispeopled of its denizens?

strength may be considered as uniform, the mean being 10,000 lb. per square inch, or upwards. From the experiments on the columns one inch square, it appears that when the height is 15 times the size of the square the strength is slightly reduced; when the height is 24 times the base, the falling off is from 138 to 96 nearly; when it is 30 times the base, the strength is reduced from 138 to 75; and when it is 40 times the base the strength is reduced to 52, or to little more than one third. These numbers will be modified to some extent by the experiments in progress. In all columns shorter than 30 times the side of the square, fracture took place by one of the ends failing; showing the ends to be the weakest parts; and the increased weakness of the longer columns over that of the shorter ones seemed to arise from the former being deflected more than the latter, and therefore exposing a smaller part of the ends to the crushing force. The cause of failure is the tendency of rigid materials to form wedges with sharp ends, these wedges splitting the body up in a manner which is always pretty nearly the same; some attempts to explain this matter theoretically were made by Coulomb. As long columns always give way first at the ends— showing that part to be the weakest-we might A law may be a rule of action, but it is not economize the material by making the areas of action. The Great First Agent may lay down a the ends larger than that of the middle, increasing rule of action for himself, and that rule may be the strength from the middle both ways towards come known to man by observation of its uni- the ends. If the area of the ends be to the area formity but constituted as our minds are, and in the middle, as the strength of a short column having that conscious knowledge of causation, is to that of a long one, we should have for a which is forced upon us by the reality of the column whose height was 24 times the breadth, distinction between intending a thing, and doing the area of the ends and middle as 13,766 to it, we can never substitute the rule for the act. 9,595 nearly. This, however, would make the Either directly, or through delegated agency, ends somewhat too strong; since the weakness whatever takes place is not merely willed, but of long columns arises from their flexure and indone, and what is done we then only declare to creasing the ends would diminish that flexure. be explained, when we can trace a process, and Another mode of increasing the strength of the show that it consists of steps analogous to those ends would be that of preventing flexure, by inwe observe in occurrences which have passed creasing the dimensions of the middle. From often enough before our own eyes to have become the experiments it would appear that the Grecian familiar, and to be termed natural. So long as columns, which seldom had their lengths more no such process can be traced and analyzed out in than about 10 times the diameter, were nearly of the this manner, so long the phenomenon is unex-form capable of bearing the greatest weight when plained, and remains equally so whatever be the their shafts were uniform; and that columns tanumber of unexplained steps inserted between its pering from the bottom to the top were only cabeginning and its end. The transition from an pable of bearing weights due to the smallest part inanimate crystal to a globule capable of such of their section, though the larger end might endless organic and intellectual development, is serve to prevent lateral thrusts. This last remark as great a step-as unexplained a one-as unin- applies, too, to the Egyptian columns, the strength telligible to us—and in any human sense of the of the column being only that of the smallest part word as miraculous as the immediate creation and of the section. From the two series of experiintroduction upon earth of every species and ments, it appeared that the strength of a short every individual would be. Take these amazing column is nearly in porportion to the area of the facts of geology which way we will, we must re-section, though the strength of the larger one is sort elsewhere than to a mere speculative law of development for their explanation.

"ON THE STRENGTH OF STONE COLUMNS," by Mr. E. Hodgkinson.-The columns were of different heights, varying from 1 inch to 40 inches; they were square uniform prisms, the sides of the bases of which were 1 inch and 13 inch, and the crushing weight was applied in the direction of the strata. From the experiments on the two series of pillars it appears that there is a falling off in strength in all columns from the shortest to the longest; but that the diminution is so small, when the height of the column is not greater than about 12 times the size of its square, that the

somewhat less than in that proportion.

Mr.

Prof. Challis inquired whether Mr. Hodgkinson had found the columns to give way chiefly in the direction of the cleavages of the stone? Hodgkinson replied that he had; and that hence the same size and shape of stone cut out of the same block, required very different forces to crush them across the grain from what they did with it

Prof. Stevelly said, that it was one peculiarity of Mr. Hodgkinson's researches, that they opened up so many collateral objects of interest and wide fields of inquiry. It was easy to see that the present researches might become important to the geologist, by leading him to the source from which originated the splitting up of extended

rocks into beds and strata, and the contortions of them; for example, to some volcanic matter forced up vertically in such a manner as to exercise a crushing force upon even distant masses.Prof. Willis showed, by examples deduced from various styles of architecture, that the ancients must have been practically in possession of similar principles; and from several examples which he gave, it would appear that columns of a shape suited to these principles were again coming into

use.

great distance; but of what genus or species had been the architect and occupant of the structure Mr Burton could not, from his own observation, determine. From the accounts of the Arabs, however, it was presumed that these nests had been occupied by remarkably large birds of the stork kind, which had deserted the coast but a short time previous to Mr. Burton's visit. To these facts," said Mr. Bonomi, "I beg to add the following remarks:-Among the most ancient records of the primeval civilization of the human race that have come down to us, there is described, GIGANTIC BIRD.-The Secretary read a pa- in the language the most universally intelligible, per from Mr. Bonomi, "On a Gigantic Bird sculp- a gigantic stork bearing, with respect to a man of tured on the Tomb of an Officer of the Household ordinary dimensions, the proportions exhibited in of Pharaoh " "In the gallery of organic remains the drawing before you, which is faithfully copied in the British Museum are two large slabs of the from the original document. It is a bird of white new red sandstone formation, on which are im- plumage, straight and large beak, long feathers pressed the footsteps or tracks of birds of various in the tail; the male bird has a tuft at the back of sizes, apparently of the stork species. These the head, and another at the breast: its habits geological specimens were obtained through the apparently gregarious. This very remarkable agency of Dr. Mantell from Dr. Deane, of Massa- painted basso-relievo is sculptured on the wall, in chusetts, by whom they were discovered in a the tomb of an officer of the household of Pharaoh quarry near Turner's Falls. There have also Shufu, (the Suphis of the Greeks,) a monarch of been discovered by Capt. Flinders, on the south the fourth dynasty, who reigned over Egypt, coast of New Holland, in King George's Bay, while yet a great part of the delta was intersected some very large nests measuring twenty-six feet by lakes overgrown with the papyrus-while yet in circumference and thirty-two inches in height; the smaller ramifications of the parent stream resembling, in dimensions, some that are descibed were inhabited by the crocodile and hippopotaby Capt. Cook, as seen by him on the north-east mos-while yet, as it would seem, that favored coast of the same island, about 15° south latitude. land had not been visited by calamity, nor the It would appear, by some communications made arts of peace disturbed by war, so the sculpture in to the editor of the Athenæum, that Prof. Hitch- these tombs intimate, for there is neither horse cock of Massachusetts had suggested that these nor instrument of war in any one of these tombs. colossal nests belonged to the Moa, or gigantic At that period, the period of the building of the bird of New Zealand; of which several species Great Pyramid, which, according to some wrihave been determined by Prof. Owen, from bones ters on Egyptian matters, was in the year 2100 sent to him from New Zealand, where the race is B. C., which, on good authority, is the 240th year now extinct, but possibly at the present time in- of the deluge, this gigantic stork was an inhabithabiting the warmer climate of New Holland, in ant of the delta, or its immediate vicinity; for, as which place both Capt. Cook, and recently Capt. these very interesting documents relate, it was Flinders, discovered these large nests. Between occasionally entrapped by the peasantry of the the years 1821 and 1823, Mr. James Burton dis- delta, and brought with other wild animals as covered on the west coast or Egyptian side of the matters of curiosity to the great landholders or Red Sea, opposite the peninsula of Mount Sinai, farmers of the products of the Nile-of which cirat a place called Gebel Ezzeit, where for a con- cumstance this painted sculpture is a representasiderable distance, the margin of the sea is inac- tion, the catching of fish and birds, which in these cessible from the Desert, three colossal nests days occupied a large portion of the inhabitants. within the space of one mile These nests were The birds and fish were salted. That this docunot in an equal state of preservation; but, from ment gives no exaggerated account of the bird one more perfect than the others, he judged them may be presumed from the just proportion that to be about fifteen feet in height, or, as he ob- the quadrupeds, in the same picture, bear to the served, the height of a camel and its rider. men who are leading them; and, from the abThese nests were composed of a mass of hetero-sence of any representation of these birds in the geneous materials, piled up in the form of a cone, and sufficiently well put together to insure adequate solidity. The diameter of the cone at its base was estimated as nearly equal to its height, and the apex, which terminated in a slight concavity, measured about two feet six inches, or three feet in diameter. The materials of which the great mass was composed were sticks and weeds, fragments of wreck, and the bones of fishes: but in one was found the thorax of a man, a silver watch made by George Prior, a London watchmaker of the last century, celebrated throughout the East, and in the nest or basin at the apex of the cone, some pieces of woolen cloth and an old shoe. That these nests had been but recently constructed was sufficiently evident from the shoe and watch of the shipwrecked pilgrim, whose tattered clothes and whitened bones were found at no

less ancient monuments of Egypt, it may also be reasonably conjectured they disappeared soon after the period of the erection of these tombs. With respect to the relation these facts bear to each other, I beg to remark that the colossal nests of Capts. Cook and Flinders, and also those of Mr. James Burton, were all on the sea-shore, and all of those about an equal distance from the equator. But whether the Egyptian birds, as described in those very ancient sculptures, bear any analogy to those recorded in the last pages of the great stone book of nature, (the new red sandstone formation,) or whether they bear analogy to any of the species determined by Prof. Owen from the New Zealand fossils, I am not qualified to say, nor is it indeed the object of this paper to discuss; the intention of which being rather to bring together these facts, and to

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