an accompaniment than a cause of the former, and that it is by the oxidation of carbon and hydrogen compounds that muscular force is supplied.

Mr. Croll has recently shown reason to believe that climate, at all events in the circumpolar and temperate zones, would depend on whether the winter of a given region occurred when the earth, at its period of greatest excentricity, was in aphelion or perihelion if the former, the annual average of temperature would be lower; if the latter, it would be higher, than when the excentricity of the earth's orbit were less, or approached more nearly to a circle. He calculates the difference in the amount of heat at the period of maximum excentricity of the earth's orbit to be as 19 to 26, according as the winter would take place when the earth was in aphelion or in perihelion. If this theory be borne out, we should approximate to a test of the time which has elapsed between different geological epochs. Mr. Croll's computation of this would make it certainly not less than 100,000 years since the last glacial epoch, a time not very long in geological chronology. When we compare with the old theories of the earth the modern view inaugurated by Lyell, your former president, and now, if not wholly, at all events to a great extent adopted, it seems strange that the referring of past changes to similar causes to those which are now in operation should have remained uninvestigated until the present century; but with this, as with other branches of knowledge, the most simple is frequently the latest view which occurs to the mind. It is much more easy to invent a Deus ex machinâ than to trace out the influence of slow, continuous change; the love of the marvellous is so much more attractive than the patient investigation of truth, that we find it prevail almost universally in the early stages of science. In geology a deluge or a volcano was supplied. In paleontology a new race was created whenever theory required it; how such new races began the theorists did not stop to inquire. Those who do not adopt some view of continuity are content to say, God willed it; but would it not be more reverent and more philosophical to inquire by observation and experiment, and to reason from induction and analogy, as to the probabilities of such frequent miraculous interventions? I know I am touching on delicate ground, and that a long time may elapse before that calm inquiry after truth which it is the object of associations like this to promote can be fully attained; but I trust that the members of this body are sufficiently free from prejudice, whatever their opinions may be, to admit an inquiry into the general question whether what we term species are, and have been, rigidly limited, and have at numerous periods been created complete and unchangeable, or whether, in some mode or other, they have not gradually and indefinitely varied, and whether the changes due to the influence of surrounding circumstances, to efforts to accommodate themselves to surrounding changes, to what is called natural selection, or to the necessity of yielding to superior force in the struggle for existence, as maintained by our illustrious countryman Darwin, have not so modified organisms as to enable them to exist under changed conditions. I am not going to put forward any theory of my own. I am not going to argue in support of any special theory, but having endeavoured to show how, as science advances, the continuity of natural phenomena becomes more apparent, it would be cowardice not to present some of the main arguments for and against continuity as applied to the history of organic beings. But the balance of experiment and opinion is against spontaneous generation. The records of life on the globe may have been destroyed by the fusion of the rocks which would otherwise have preserved them, or by crystallization after hydrothermal action. The earlier forms may have existed at a period when this planet was in course of formation, or being segregated or detached from other worlds or systems. We have not evidence enough to speculate on the subject, but by time and patience we may acquire it. Were all the forms which have existed embalmed in rock the question

would be solved; but what a small proportion of extinct forms is so preserved, and must be, if we consider the circumstances necessary to fossilize organic remains! The opponents of continuity lay all stress on the lost and none on the existing links. But there is another difficulty in the way of tracing a given organism to its parent form, which, from our conventional mode of tracing genealogies, is never looked upon in its proper light. Where are we to look for the remote ancestors of a given form? From the long-continued conventional habit of tracing pedigrees through the male ancestor we forget, in talking of progenitors, that each individual has a mother as well as a father, and there is no reason to suppose that he has in him less of the blood of the one than of the other. The recent discoveries in paleontology show us that man existed on this planet at an epoch far anterior to that commonly assigned to him. The instruments connected with human remains, and indisputably the work of human hands, show that to these remote periods the term civilization could hardly be applied. A little step-by-step reasoning will convince the unprejudiced that what we call civilization must have been a gradual process; can it be supposed that the inhabitants of Central America or of Egypt suddenly, and what is termed instinctively, built their cities, carved and ornamented their monuments? if not, if they must have learned to construct such erections, did it not take time to acquire such learning, to invent tools as occasion required, contrivances to raise weights, rules or laws by which men acted in concert to effect the design? Did not all this require time? and if, as the evidence of historical times shows, invention marches with a geometrical progression, how slow must have been the earlier steps! If even now habit, and prejudice resulting therefrom, vested interest, &c., retard for some time the general application of a new invention, what must have been the degree of retardation among the comparatively uneducated beings which then existed? Perhaps the most convincing argument in favour of continuity which could be presented to a doubting mind would be the difficulty it would feel in representing to itself any per saltum act of nature. Who would not be astonished at beholding an oak tree spring up in a day, and not from seed or shoot? We are forced by experience, though often unconsciously, to believe in continuity as to all effects now taking place; if any one of them be anomalous, we endeavour, by tracing its history and concomitant circumstances, to find its cause, i e., to relate it to antecedent phenomena; are we then to reject similar inquiries as to the past? Is it laudable to seek an explanation of present changes by observation, experiment, and analogy, and yet reprehensible to apply the same mode of investigation to the past history of the earth and of the organic remains embalmed in it? If we disbelieve in sudden creations of matter or force, in the sudden formation of complex organisms now-if we now assign to the heat of the sun an action enabling vegetables to live by assimilating gases and amorphous earths into growing structures, why should such effects not have taken place in earlier periods of the world's history, when the sun shone as now, and when the same materials existed for his rays to fall upon? If we are satisfied that continuity is a law of nature, the true expression of the action of Almighty Power, then, though we may humbly confess our inability to explain why matter is impressed with this gradual tendency to structural formation, we should cease to look for special interventions of creative power in changes which are difficult to understand, because, being removed from us in time, their concomitants are lost; we should endeavour from the relics to evoke their history, and when we find a gap not try to bridge it over with a miracle. Philosophy ought to have no likes or dislikes. Truth is her only aim. But if a glow of admiration be permitted to a physical inquirer, to my mind a far more exquisite sense of the beautiful is conveyed by the orderly development, by the necessary inter-relation and inter-action of each element of the cosmos, and by the conviction that a bullet falling to the

ground changes the dynamical conditions of the universe, than can be conveyed by mysteries, by convulsions, or by cataclysms. But the doctrine of continuity is not solely applicable to physical inquiries. The same modes of thought which lead us to see continuity in the field of the microscope as in the universe, in infinity downwards as in infinity upwards, will lead us to see it in the history of our own race; the revolutionary ideas of the so-called natural rights of man, and à priori reasoning from what are termed first principles, are far more unsound, and give us far less ground for improvement of the race, than the study of the gradual progressive changes arising from changed circumstances, changed wants, changed habits. Our language, our social institutions, our laws, the constitution of which we are proud, are the growth of time, the product of slow adaptations, resulting from continuous struggles. Happily in this country, though our philosophical writers do not always recognize it, practical experience has taught us to improve rather than remodel; we follow the law of nature, and avoid cataclysms. The superiority of man over other animals inhabiting this planet, of civilized over savage man, and of the more civilized over the less civilized, is proportioned to the extent which his thought can grasp of the past and of the future. His memory reaches farther back, his capability of prediction reaches farther forward, in proportion as his knowledge increases. He has not only personal memory, which brings to his mind at will the events of his individual life; he has history, the memory of the race; he has geology, the history of the planet; he has astronomy, the geology of other worlds. Whence does the conviction, to which I have alluded, that each material form bears in itself the records of its past history, arise? Is it not from the belief in continuity? Does not the worn hollow on the rock record the action of the tide, its stratified layers the slow deposition by which it was formed, the organic remains imbedded in it the beings living at the times these layers were deposited, so that from a fragment of stone we can get the history of a period myriads of years ago? From a fragment of bronze we may get the history of our race at a period antecedent to tradition. As science advances, our power of reading this history improves and is extended. Saturn's ring may help us to a knowledge of how our solar system developed itself, for it as surely contains that history as the rock contains the record of its own formation. By this patient investigation how much have we already learned, which the most civilized of ancient human races ignored! While in ethics, in politics, in poetry, in sculpture, in painting, we have scarcely, if at all, advanced beyond the highest intellects of ancient Greece or Italy, how great are the steps we have made in physical science and its applications! But how much more may we not expect to know? We, this evening assembled, ephemera as we are, have learned by transmitted labour, to weigh, as in a balance, other worlds larger and heavier than our own, to know the length of their days and years, to measure their enormous distance from us and from each other, to detect and accurately ascertain the influence they have on the movements of our world and on each other, and to discover the substances of which they are composed; may we not fairly hope that similar methods of research to those which have taught us so much may give our race further information, until problems relating not only to remote worlds, but possibly to organic and sentient beings which may inhabit them, problems which it might now seem wildly visionary to enunciate, may be solved by progressive improvements in the modes of applying observation and experiment, induction and deduction ?

At the conclusion of the President's address, Lord Belper proposed, and the Mayor of Nottingham seconded, a vote of thanks, which was carried by acclamation.

The Inquirer.