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devoted to the science of geology. Italy appears to be the first country that bestowed any direct attention to the subject of geology; although it is evident, from the writings of the ancients, that they were acquainted with the more striking phenomena of geology. Amongst those celebrated men, whose claims to the honour of having been the earliest patrons of this science, is Leibnitz, whose sagacity enabled him to lay down fundamental principles connected with geology, which, up to the present time, have not been invalidated. Our countryman, Hooke, also well deserves to have his name mentioned with that of Leibnitz, as another great supporter of the infant science. Werner was the first that reduced what was known of geology to a system, and was lucky in being supplied with a great abundance of materials from the labours of Saussure and other inquirers. By degrees geology was cultivated through the continent, and the light which was thrown upon it by those who pursued the fossil department, such as Cuvier, gave an interest to the study, which has contributed to diffuse it very generally amongst every class of the community. .

Anxious merely to present our readers with the materials for enabling them to judge of the objects and views of the New Society, we have confined our attention to the leading subjects treated of in the volume before us. We have thus left unnoticed a great mass of curious and important facts, which lie scattered through the notices and abstracts.

Perhaps there never was an institution, professing to have in view the promotion of science, at which the general body of the intelligent of all classes have more reason to be proud, than that of the British Association for the Advancement of Science. The principles by which it is to be guided, and the men on whom the responsibility of its protection has devolved, need only be known in order to excite the strongest assurances of success. The personages who have volunteered their services in the foundation of the society may be justly described as amongst the elite of our country; and a better idea of the authority which they maintain in the field cf science could not be afforded than in the declaration of Professor Airy, of Cambridge, who stated, that no inducement whatever, save that of such a solicitation as he had received, would have impelled him to undertake the task which he fulfilled in his elaborate report on astronomy. Such are the auspices, so far as character is concerned, under which the society has commenced its existence ; and the constitution on which its proceedings are to be conducted are in every way worthy of the high intelligence in which the plan of that constitution originated. The society contemplates no interference with the ground already occupied by other institutiuns, its sole objects being to give, what were exceedingly much wanted before, a more systematic direction to scientific inquiry-to promote the intercourse of those who cultivate science, not only in different parts of the British empire, but of foreign philosophers

with the latter ; and, finally, to endeavour to make science more extensively popular than it is, and to take every pains for removing the obstructions of a public nature which may be found to impede the advancement of sound knowledge. The spirit with which the society is actuated, will be found more fully developed in the following extract from the Report of the Council of the Yorkshire Philosophical Society:

The object of this system is not only to give connection to the efforts of insulated inquirers, but to link societies themselves together in unity of purpose, and in a common participation and division of labour. There are many important questions in philosophy, and some whole departments of science, the data of which are geographically distributed, and require to be collected by local observations extended over a whole country; and this is true, not only of those facts on which single sciences are founded, but of many which are of more enlarged application. Thus, for instance, were the elevation above the sea of all the low levels, and chief heights and eminences, of a country ascertained so generally, that every observer of nature might have a station within his reach from which he could fix the relative position in this respect of whatever might be the object of his research,-of how many questions, in how many sciences, would these facts contribute to the solution ? Again, supposing it to be ascertained also, at these stations, what is the temperature of the air, and of the water,-as it falls from the sky, and as it is held in the reservoirs of the earth,—these are data of the same kind, interesting not only to meteorological science, but to the philosophy of organized and animated existence. Yet, extensive as might be the importance of such facts, and simple as are the processes for ascertaining them, and numerous as are the individuals capable of contributing to their investigation, how little, nevertheless, even of this elementary work has yet been accomplished, either by insulated observers, or by those who are associated together for the express purpose of advancing the sciences to which it is of such essential interest.

“ None of our societies has ever pretended to collect observations of this kind on a regular system, nor to form a national catalogue of the scattered particulars of any one science, accurately detailed ; and yet the great value which would attach to such collections of facts, when reduced and analysed, must often have occurred to the enlightened conductors of such institutions; but that which has prevented any single society from venturing on the undertaking, lias been the impracticability of carrying it on over so extensive a territory as an entire kingdom. There is a method, however, by which these important objects might be achieved. Were there in every county one or more provincial societies, having some members competent to superintend, and others ready to execute, the observations within defined limits, and were these societies willing to work together on a common plan, the natural history of the country, and all the geographical data of philosophy included within it, might easily be collected in a manner far more perfect than has ever yet been attempted.

"With a just sense, therefore, of the consequence to science of combining the Philosophical Societies dispersed through the provinces of the empire in a general co-operative union, the British Association has not only invited them to join its meetings, but has given to those whom they may specially depute to represent by them, the privilege of becoming members of the committee by which its affairs are conducted

“ It appears to the Council that in availing themselves of the bond of connection thus offered, Societies will not only contribute most essentially to the success of this extensive plan, but will add greatly to their own efficiency. When individuals meet for scientific objects, the effect of the general effort, emulation, and example, is to produce a spirit of exertion, which gives to such meetings their principal value. And if Societies shall concur in thus meeting each other, in proposing certain common objects, in communicating from year to year the means which they are employing and the progress which they are making,-it seems impossible that this should be done in the presence of an assembly concentrating a great part of the scientific talent of the nation, without kindling an increased ardour of emulous activity; it seems impossible that the deputies of any Society should attend such meetings without bringing back into its bosom an enlargement of views, and communicating to its members new lights of knowledge, new motives for inquiry, and new encouragement to perseverance.

“The actual assembling of one of the meetings at the place in which any Society is established, has a tendency to produce the same effect in a still more powerful degree, and the Council does not hesitate to state that this institution has received a sensible impulse in all these respects, from the visit with which it has recently been honoured. The plan indeed on which it was first founded, and on which it has been since conducted, was in the spirit of the design which may now be contemplated for the whole kingdom. Its especial aim has been to collect information respecting its own county, and the end to which it aspires has been described in a former Report to be the execution of such a History of Yorkshire as the Natural Philosopher and the Antiquary may be contented to possess. But how greatly will the importance of this object be heightened, when it is incorporated into a national system, and when all the results of our inquiries become part of the materials of a far more extensive analysis. It could not but be felt before by a provincial Society, that, in executing the task which it had undertaken, advice and consultation were wanted. With how much more confidence may it proceed when it has the advantage of consulting with the Committee of this great national Association. In comparing the views which it entertains, and the methods which it employs, with those that may be offered to its consideration, how largely may it profit by such a commerce, without sacrificing any portion of its real dignity or independence.”

In noticing, as it is our duty to do, the works which occasionally issue from the press on the various branches of science, it frequently happens to us to find great difficulty in determining the extent to which we may carry our account of their contents, so as to do justice to the author, without, at the same time, burthening our pages with matter which may not be suited to the great majority of our readers. A crisis of this nature would have arisen on the present occasion, when we have to communicate some notion to the public of the nature and merits of the two works on geology, whose titles are enumerated at the head of the present article, were it not that the field of observation thus presented to us were much

too extensive to be completely traversed by us at this opportunity. We must be content, therefore, with simply specifying such portions of either work as are calculated to be rendered intelligible to the general reader.

The Introduction of Mr. Bakewell has now attained a fourth edition, a circumstance which is itself sufficient to prove the merits of the production. The improvements introduced into this edition, and which distinguish it froin the last, are numerous and important, and may be regarded as a measure of the extraordinary rapidity with which geological discoveries are daily increasing. The present edition, then, possesses very considerable advantages over all its predecessors, not only in the greater abundance of information, but also in the amount of the graphic illustrations, and particularly in the greater accuracy with which the different descriptions are now given. Mr. Bakewell states, that as a preparation for this edition, he has deemed it necessary to revisit the scenes of his earliest investigations, and to examine with his own eyes certain parts of England, of which the geology was doubtful. With the results of these investigations the author has added whatever of value, connected with the subject, which he could find in the labours of various geologists, British and foreign, within the last five years. Amongst the novelties by which the present edition is characterised, is the subject of fossil conchology, which the author treats with great caution and judgment. Some of the more speculative of the French conchologists are endeavouring to establish, that fossil con. chology, independent of the succession and stratification of rocks, is the only true basis of geology. Our author sets his face against all such fanciful theories, and expresses a hope, that the enlightened Boué, who is engaged in an effort to resist the absurd attempt, will be supported by the encouragement of all true geologists.

The scientific world is greatly indebted to Mr. Mantell, of Lewes, for the success with which he has investigated the geological structure of the south-eastern portion of England. For a long period, it was the opinion of geologists, particularly of those of foreign countries, that there was little or nothing worthy of scientific attention in the structure of the surface of England. But the labours of Mr. Mantell have proved how very contrary to the truth are these assertions, and it has been the good fortune of this gentleman to show, that the facts connected with the geological structure of the county of Sussex are as interesting and important in displaying the principles on which the changes of the earth's surface have taken place, as any discoveries of which the annals of this science can boast. We could scarcely hope to employ the reader's attention profitably to himself, were we to attempt to explain the train of discoveries which Mr. Mantell has set forth in this volume. We must be satisfied with referring the reader to the work itself, in which he will find the materials for solemn and lasting meditation, conveyed in language worthy the great subject. Indeed, in none

of the productions which geologists have put forth do we find the principles of the difficult science more plainly or more forcibly laid down than in the volume of Mr. Mantell; and though the book is nominally limited to the districts of the south-eastern quarter of England, it is substantially a key of the most easy application to the general doctrines of geology. As we have not met with any view of the nature of this science which seems to embrace so many good qualities as that of Mr. Mantell, we shall give the reader below the benefit of his truly philosophical description.

Of the whole superfices of the earth, amounting to one hundred and ninety millions of square miles, not more than a fifth of the space is appropriated to the residence of man and the terrestrial animals. The strata composing the earth have been examined through a thickness of nearly eight miles, calculating from the summits of the highest mountains to the greatest depths, whether natural or artificial. Now the eight miles depth of strata, as compared with the size of the earth, bears the same proportion to what it covers as does the external paper which envelopes a common globe, and if we regard the fissures and elevations upon this surface of the artificial globe, we shall have a good idea of the mountains and valleys formed by and in the strata of eight miles depth of the earth. It follows from this statement, that disturbances of the earth's surface may have taken place to a far greater depth without extending themselves to the whole of the mass, and thus at once the difficulty will be got over, which opposes the probability of the facts presented by geological science being true. The inquirer acquainted with these preliminary facts, will not hesitate to believe, that he sees in the displacements and fractures of the surface, the effects produced by the earthquake and the volcano; whilst in the water-worn materials, such as the beds of gravel, he will recognise the evidence of the agency of aqueous elements. The mineral masses forming the crust of the earth, may, for the sake of clearness, be classed into two grand divisions, the primary and the secondary. The first are chiefly of igneous origin, and contain no organic remains; whilst the latter are the result of sedimentary deposits, and in them are found organic remains. The secondary rocks, however, are themselves divided, for the convenience of study, into secondary, properly so called, and tertiary. The formations of this secondary class compose the surface of the southeast of England.

In this strata are found remains of animals and vegetables, which afford the most undoubted proofs that a state of animated nature has once existed, which is widely different from that with which we are now surrounded.

By these relics (observes Mr. Mantell), these medals, as they have been aptly termec, struck by nature to commemorate her revolutions, we learn the physical inutations which the surface of the earth has undergone, and

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