tion must be employed in supplying such articles to our encyclopædias. But though the opinion of Sir James Mackintosh is, generally speaking, well founded, and is likely to be so as to encyclopædias of secondary character, yet there are cases, such as that of the work before us, in which the literary and political articles stand on the same high level as those of the mathematical and physical sciences.* When the resources of the proprietors are sufficient to command the services of such writers as Young, Malthus, Macculloch, Roget, Wilson, Empson, and Tytler, while the editor can count on the aid of friends like Scott, Playfair, Stewart, Leslie, Lord Jeffrey, Sir William Hamilton, and Sir John Barrow,-it is not difficult to anticipate the result. In the mathematical and physical department of this work we find a combination of theoretical and experimental talent which has never before been directed in the same channel. While the treatises of Robison, Playfair, Mr. Ivory, M. Biot, Dr. Young, and Mr. Galloway, have recorded the most recent discoveries in astronomy, those of Robison, Young, M. Arago, Sir David Brewster, Dr. Roget and Dr. Trail, exhibit to us a full view of those recent and splendid discoveries by which optics has become almost a new science. In the articles on Acoustics, Dynamics, Mechanics, Hydrodynamics, Pneumatics, Electricity, Magnetism, and Voltaic Electricity (including the interesting new sciences of Electromagnetism, Magneto-electricity, and Thermo-electricity), which complete the circle of Natural Philosophy, we find the fullest details respecting the fine discoveries of Coulomb, Volta, Oersted, Seebeck, Ampère, and Faraday; while the articles Chemistry and Heat, contributed by Dr. Thomson and Dr. Trail, exhibit to us the recent discoveries of Davy, Berzelius, Faraday, Leslie, Melloni, and Forbes. Were we to claim for several treatises in this Encyclopædia' a superiority merely over separate works on the same subjects, we should not be doing justice to their merits. There are many subjects treated of in encyclopædias, on which no separate treatise at all has been written; and the student often searches in vain for the know ledge which he requires. There are other subjects upon which no eminent writer has *It is not necessary for us to remind our readers of the extraordinary literary talent which pervades very many articles of the Encyclopædia Metropolitana,' and also of the 'Edinburgh Encyclopædia,' completed some years ago under the editorship of Sir David Brewster. written a separate work, and, in those cases in which such works do exist, they have seldom been brought down to the present day, or drawn up with that copious detail of recent discoveries which is of so much importance to the progress of science. It is often in articles contributed by eminent individuals who have made the subjects of them their particular study that we have our only chance of finding the inestimable treasures of contemporary discovery which fill the 'Transactions' of domestic and foreign societies, and those less elaborate notices of experimental researches, circulated by numberless periodical journals, which are the depositories of American as well as European science. arts But these observations are still more applicable to the scientific arts-the which have science for their basis and for their object to the manufactures and useful arts, and to those new and important subjects which are included under the general head of Civil Engineering. Upon the greater number of these topics no separate works have been written, so that it is only in the storehouse of an encyclopædia that the general reader can find the information on such subjects which is so frequently required. In this department the Encyclopædia Britannica is particularly rich, and especially as to those new arts which are on the eve of altering the forms and habits of social life. The wonders of railway intercourse, of locomotive engines, tunnels, steam-printing, steam-boats, and steamguns; the improvements in gas-lighting, and lighthouses; the almost magical arts of the electrotype, voltaic gilding and plating, and the powers of the electro-magnetic telegraph and the electro-magnetic clock, are all treated in this work by writers competent to the task. It is impossible to refer to these new arts, which, along with the Daguerreotype of Niepcé and Daguerre and the Calotype of Mr. Fox Talbot, constitute the leading inventions of the day, without giving our readers some slight notice of them. There is perhaps none of the sciences, with the exception of chemistry, which has made such donations to the fine and useful arts as voltaic electricity. Those which depend upon galvanism, or voltaic electricity, properly so called, are Sir H. Davy's art of protecting the copper-sheathing of ships; the galvano-plastic art of Spencer and Jacobi for multiplying works of art in metal; electro-metallurgy, or the reduction of metals by electricity; the electrotype, or art of copying and multiplying engrav . ings; and the arts of voltaic etching, gild-1 ing, and plating. The art of multiplying works in metal was invented in 1831, nearly about the same time, by M. Jacobi of St. Petersburg and Mr. Spencer of Liverpool. It consists of depositing copper, gold, silver, and platinum, &c., from their solutions, upon metallic or conducting surfaces, the metal being precipitated by galvanism. If the surface is that of an intaglio, we obtain from it a perfect cameo, and vice versa. In 1840 Mr. Murray announced the important fact, that these metals could be all precipitated upon non-conducting substances, such as plaster of Paris, wax, wood, &c., by previously metallising their surface with black lead. In this way, every work formed by art, whether it be the finest carvings, or the finest sculptures, can be multiplied in copper, or the other metals already mentioned. The multiplication of engraved copper-plates is another of the triumphs of this new art; and engravers have found that plain copper-plates deposited from a solution of sulphate of copper upon another previously prepared copper surface, are far superior to those manufactured in the usual way. The art of voltaic etching is singularly beautiful. A copper-plate prepared for ordinary etching, and all covered with wax, is connected with a suitable galvanic battery, and placed in a solution of sulphate of copper. A piece of copper (negative) of the same size as the copper-plate is then connected with the zinc. When the battery is put in action, copper is reduced from the solution on the negative piece of copper, while copper is removed from the clear lines of the etching-plate to supply what is taken away from the solution. In this process no nitrous fumes annoy the artist, and no air-bubbles interfere with the precision of his work. The lines may be bitten to any depth, and are much sharper and clearer than when they are made with an acid. The art of gilding upon silver and brass, which we owe to M. Delarive of Geneva, is equally beautiful and important. The gold is deposited in coatings of any thickness from a weak nitro-muriatic solution of it, and the deleterious effects of mercury upon the artist are thus completely avoided.* The modern arts presented to us by electro-magnetism, the new science of Oersted and Ampère, are not less wonderful and valuable. The electro-magnetic telegraph of Professor Wheatstone, now in use upon the Blackwall and the Great Western railways, was the first of these achievements. The telegraph, with its accompanying alarums, goes into a case not larger than that of a small table cloth, and so simple are its assertions, that any child can both read and send the messages with scarcely a minute's instruction. The electro-magnetic clock of Professor Wheatstone is another of those singular inventions, and one which, though it may be less useful, is certainly not less ingenious and surprising than his telegraph. The object of the inventor was to enable a single clock to indicate exactly the same time in as many different places, distant from each other, as may be required. A standard clock in an observatory, for example, would thus keep in order another clock in each apartment, and that too with such accuracy that all of them, however numerous, will beat dead seconds audibly, with as great precision as the standard astronomical timepiece with which they are connected. But, beside this, the subordinate timepieces thus regulated require none of the mechanism for maintaining or regulating the power. consist simply of a face with its second, minute, and hour hands, and of a train of wheels which communicate motion from the action of the second-hand to that of the hour-hand, in the same manner as an ordinary clock train. Nor is this invention confined to observatories and large establishments. The great horologe of St. Paul's might, by a suitable network of wires, or even by the existing metallic pipes of the metropolis, be made to command and regulate all the other steeple-clocks in the city, and even every clock within the precincts of its metallic bounds. When railways and telegraphs extend from London to the remotest cities and villages, the sen They in gold and silver, such as vases, chandelier branches, &c., by depositing the metal upon proper models, which may be afterwards removed from the silver and gold articles, by displacement, heat, or solution; and Mr. Edward Palmer has secured by patent another invention equally important. He obtains printing surfaces by drawing or painting on silver or copper, or any other conducting surface, and then, by the electrotype, he produces copper or other metallic plates with sunken surfaces from which prints may be taken, or from engraved copper plates. Mr. Palmer calls this art Electro-tinting, and he proposes to employ it for printing china, pottery ware, music, maps, and portraits. See, Newton's London Journal and Repertory of Arts' for April, 1842, vol. xx., pp. 166, 171, 172. perish. sation of time may be transmitted along, mighty sarcophagi of the brutes that with the elements of language; and the great cerebellum of the metropolis may thus constrain by its sympathies, and regulate by its power, the whole nervous system of the empire. In the other departments of the useful arts where profound science is called into exercise, we have the articles on Arch, Carpentry, and Centre, River, Roofs, Strength of Materials, and Water-works, by Robison; Seamanship, by the same, with a skilful supplement by Capt. B. Hall; Bridges and Roads, by Young; Architecture and Building, both very able papers, by Mr. Hosking, Professor of Architecture in King's College, London; Breakwaters and Docks, by Sir John Barrow; Shipbuilding (by far the best Essay on the subject in the language,) by Mr. Creuze, of Portsmouth; Cotton Manufacture, by Mr. Bannatyne; Weaving and Woollen Manufacture, by Mr. Chapman, &c. &c. It was to be expected, therefore, that the sciences of Geology, Zoology, and Botany, should be most carefully and completely treated of in such a work as this. They form, indeed, the key to the hieroglyphics of the ancient world; they enable us to reckon up its almost countless periods; to replace its upheaved and dislocated strata ; to replant its forests; to reconstruct the products of its charnel-house; to repeople its jungles with their gigantic denizens; to restore the condors to its atmosphere, and give back to the ocean its mighty leviathans. And such is the force with which these revivals are presented to our judgment, that we almost see the mammoth, the megatherion, and the mastodon, stalking over the plains or pressing through the thickets; the giant ostrich leaving its footwriting on the sands; the voracious ichthyosaurian swallowing the very meal Among the subjects that must enter which its fossil ribs enclose; the monstrous largely into the composition of an Ency- plesiosaurus paddling through the ocean, clopædia are those which constitute what and guiding its lizard-trunk, and rearing its may be called Terrestrial Physics, includ- swan-neck, as if in derision of human wising the structure and physical history of dom; and the ptero-dactyle, that mysteriour globe and of its atmosphere, and an ous compound of birds, and brutes, and account of the various organized bodies bats, asserting its triple claim to the occuwhich it contains or produces. This spe-pancy of earth, ocean, and atmosphere. cies of knowledge is, generally speaking, In the elegant and comprehensive hismost fascinating. It requires little previ- tory of the ANIMAL KINGDOM, by Mr. ous preparation of the mind; it is associat- James Wilson, he adopts, as the principle ed with our wants and amusements, and upon which the various articles of Natural finds frequent and useful application in all History are to be treated, the scientific clasthe various conditions of life. Carrying sification of Cuvier, who divides the Anius back into the depths of time long be- mal Kingdom into four great classes: Verfore the dawn even of fabulous history, tebrate Animals, or those which have backmodern Geology has acquired an interest bones; Molluscous Animals, such as shellexceeding, perhaps, that of any other of fish and snails; Articulated Animals, such the physical sciences. Though her conclu- as earth-worms, lobsters, spiders, and insions have not the evidence of demonstra-sects; and Radiated Animals, such as startion, and are opposed to many of our early fish, intestinal worms, sea-nettles, corals, prejudices, yet they stand before us in the sponges, and infusory animalcules. In virgrandeur of truth, and have commanded tue of this arrangement the vertebrated anthe assent of the most pious and sober-imals are described under the heads ICHminded of our philosophers. They have THYOLOGY, MAMMALIA, ORNITHOLOGY, and lent, in fact, a new evidence to Revealed REPTILES; the molluscous animals under Religion; they have broken the arms of the article MOLLUSCA, written by a most the skeptic; and when we ponder over the great events which they proclaim,-the mighty revolutions which they indicatethe wrecks of successive creations which they display-and the immeasurable cycles of their chronology-the era of man shrinks into contracted dimensions; his proudest and most ancient dynasties wear the aspect of upstart and ephemeral groups; the fabrics of human power, the gorgeous temple, the monumental bronze, the regal pyramid, sink into insignificance beside the distinguished naturalist, Dr. Fleming; the articulated animals under the heads of ARACHNIDES, CRUSTACEA, and ENTOMOLOGY; and the fourth class under the words ANIMALCULE, ECHINODERMATA, HELMINTHOLOGY, and ZOOPHYTES. The great body of these valuable treatises we owe to Mr. Wilson himself, and the rest were executed under his immediate superintendence, in order to give variety and symmetry to the whole system of natural knowledge. In connection with this branch of science we may here mention the popular article on ANGLING, Written by the same author;* and the articles HORSE, HORSEMANSHIP, HOUND, and HUNTING, from the pen of Mr. Apperley (Nimrod,) whose powers of blending amusement with instruction are well known to the readers of this journal. Among the productions of the natural world plants stand next to animals in their relation to the purposes of domestic life. The great botanist of our age, the late Sir James Edward Smith, drew up an interesting history of BOTANY and BOTANICAL SYSTEMS, which Dr. Walker Arnott has judiciously introduced into his valuable article on BOTANY; and the remarkable treatise on the anatomy and physiology of vegetables (enlarged by Professor Balfour,) we owe to the late Mr. Daniel Ellis, whose fine talents and philosophical cast of mind characterize this elaborate article. The newest though not the least important of the natural sciences, namely GEOLOGY, with MINERALOGY as its handmaid, has been treated in a manner corresponding to its importance. The treatise on GEOLOGY was composed by Mr. John Phillips, a geologist of the first rank, and whose general knowledge added a new qualification for the task. We regard this essay as one of high merit, containing a systematic and philosophical view of the extensive subject of which it treats, while at the same time it is so perspicuous in its language, and so sober in its views, that the general reader cannot fail to peruse it with pleasure and satisfaction. The recent discoveries of Cuvier, Smith, Buckland, Sedgwick, Murchison, Conybeare, Lyell, Hibbert, Elie de Beaumont, Fourier, and Agassiz, are all brought before us in a condensed form; and by means of constant references to the original works we can appeal to them for any further details which may be desired. Of MINERALOGY it is enough to say that it is treated by Professor Jameson. Under the head of terrestrial physics, already referred to, we may include AGRICULTURE, HORTICULTURE, PHYSICAL GEOGRAPHY, and METEOROLOGY, articles contributed by Mr. Cleghorn, Dr. Neill, Dr. Trail, and Sir John Leslie, and marked by the same industry and talent which characterize the more scientific department of the general subject. From the physical sciences, the philosophy of matter, we must now turn to the philosophy of the mind-that science which This entertaining manual has been published separately, and was reviewed by us in connection with Mr. Colquhoun's 'Moor and Loch' about a year ago. VOL. LXX. 5 has not yet taken its place within the domain of positive knowledge. It is impossible to read the interesting details of its history, to follow its ingenious and varied speculations, and to weigh the conclusions at which its votaries have arrived, without endeavouring to estimate the value and extent of its acquisitions, and without fearing that a value too high has been placed upon them, and an extent too wide assigned them. The learned and beautiful dissertation of Dugald Stewart is peculiarly fitted to assist the student in this inquiry. We gaze with delight on the first dawnings of intellectual truth; we admire it as it brightens amid the clouds and storms of controversy; we follow it with straining eye till it is eclipsed in the superstition and darkness of the middle ages; we trace its revival amid the congenial gleams of literature and physical science; and we pursue it through all the lights and shadows of modern controversy, till our labouring reason abandons her pursuit amidst the 'cloud-capped metaphysics of the German school.' In this survey of its Own powers the mind is bewildered among conflicting opinions. The truths of one age appear to have been the errors of the next; the lights of one school become the beacons of its rival; and amid the mass of ingenious speculation, and the array of ambiguous facts to which the inductive process can scarcely be applied, we seek in vain for distinct propositions and general laws. If that only can be called truth which we can compel a sound and unprejudiced mind to believe, we are driven to the conclusion that our intellectual philosophy cannot yet boast of the number of her achievements. Even in that department which relates to the functions and indications of the senses, where physical science comes powerfully to our aid, there is but little harmony among the opinions of our most distinguished metaphysicians; and many of those points which Reid and Stewart were considered to have placed beyond the reach of scepticism have been lately assailed with the keenest ingenuity by their own countryman, Dr. Thomas Brown. How much more difficult, then, must it be to establish incontrovertible truths when the phenomena are those of thought. and consciousness, and the sole instrument of research by which we take cognizance of them is the abstract power of reflection. In support of these views we may adduce the observation of Dr. Reid himself, that the system which is now generally received with regard to the mind and its operations derives not only its spirit from Descartes, but its fundamental principles; and that, after all the improvements made by Malebranche, Locke, Berkeley, and Hume, | placed it beyond a doubt that the Egyptian it may be called the Cartesian system.' In hieroglyphics were signs of sounds, and quoting this passage Mr. Stewart adds that had determined the phonetic signs of seven the part of the Cartesian system here allud- of the letters of the alphabet. Dr. Young, ed to, is the hypothesis, that the communica- however, did not perceive the whole value tion between the mind and external objects of this step: in consequence of his having is carried on by means of ideas or ima-limited his principle to foreign sounds he ges. was prevented from pursuing it to its results; and he thus left to M. Champollion the honour of illustrating and developing the discovery. The English philosopher, however, pushed his researches in a different direction, and succeeded in constructing an enchorial alphabet, and presenting it to the world in a state so complete, that but few additions have been made to it by his successors. These discoveries, with a full account of the labours of Champollion and others, are admirably expounded in the article HIEROGLYPHICS, which, with the exception of the 3d, 4th, and 5th sections by Dr. Young, was written by the late Dr. Browne. We owe to Dr. Young, also, the treatise on the affinity of languages, which forms the 2d section of the able article on Lan But whatever estimate we may form of the nature and extent of our knowledge of mental phenomena, there can be only one opinion of the high interest and vast importance of the subject; and the treatises on its various branches in the Encyclopædia' will be found extremely valuable and instructive. In Dr. Hampden's lives of ARISTOTLE, PLATo, and SOCRATES-(though we cannot exactly place them on the same very high level with his article on Thomas Aquinas, in the Encyclopædia Metropolitana)—the student will obtain a clever and comprehensive view of the ancient philosophy; and in the articles on UNIVERSAL GRAMMAR, METAPHYSICS, and PHILOSOPHY, the two last of which were written by Bishop Gleig and Professor Robison, he will find the general sub-guage. ject discussed in its most important bearings, while the preliminary dissertation on metaphysical and ethical philosophy will place before him in ample detail an interesting history of the progress of opinion in these branches of knowledge. The subject of general literature, including antiquities and the fine arts, has been treated in the Encyclopædia Britannica' in a manner not on the whole less satisfactory. The articles on CHIVALRY, DRAMA, and ROMANCE, by Sir Walter Scott, are worthy of that name. The last of those articles having been limited to romances of chivalry, it has been extended very ably by Mr. Moir, so as to embrace a critical account of the romances of the Great Novelist himself, and others of anterior and subsequent date. The treatise on BEAUTY by Lord Jeffrey exhibits that intellectual power, elegant taste, and brilliant diction, by which so many of his productions have been distinguished. The treatises on Music by Mr. Grahame, on PAINTING by Mr. Haydon, on POETRY by Mr. 'Moore, and on RHETORIC by Mr. Spalding, are all skilful performances, not unworthy of being associated with this masterly Essay. But there is another department of general literature almost of modern growth in which the Encyclopædia' may boast of its exclusive superiority. The discoveries of Dr. Thomas Young respecting hieroglyphics have been justly considered as among the highest achievements of modern learning So early as 1818 our great countryman had In the circle of human knowledge HisTORY and BIOGRAPHY form one of the largest and most popular departments; and it is here that the peculiar advantages of encyclopaedic instruction most strikingly appear. The histories of the various nations of the world, both ancient and modern, though written on different scales, and by a variety of hands, form, nevertheless, a body of universal history which a hundred separate volumes would not be able to supply. In this class of articles we find the most recent information, and we are able to read the events of our own time with a copiousness and minuteness of detail which we should look for in vain in the independent histories of European states. greater number of historical articles have been composed by authors well known to the public; and the History of SCOTLAND, by Mr. Tytler, is not the only one that presents in a condensed form the results of years of study devoted to a particular subject. The The biographical department has also been elaborately prepared. Many very interesting lives were written by Dr. Thomas Young; the greater number of the articles in classical and mythological biography were composed by Mr. Ramage; and almost all the Scottish lives were re-composed by that well-read, modest veteran, Dr. David Irving. The memoirs of Schiller, Shakspeare, and Pope, by Mr. De Quincey, have been much admired as specimens of critical biography; and among |