a full account of a philosopher whose researches have been very much slighted by English mathematicians. Atmosphere is valuable as far as it goes, but the theories and observations of some modern writers of great merit are not noticed. Aurora borealis contains a very full, complete, and methodized account of the state of knowledge relative to this beautiful and curious phenomenon. Barometer is composed in the exhaustive German style, and will be resorted to by authors of less research as an invaluable treasure. There are some agricultural articles in the volume before us, which although written, as an American would say, lengthily, possess, however, much intrinsic merit. The question concerning the effect of ashes as a manure is remarkably well discussed the cultivation of barley, and the construction of barns, are also ably and usefully treated of. : In mineralogy there is no article that particularly demands notice; and the only chemical subjects of importance are azot and balsams. Bark in vegetable physiology is an interesting subject, and is noticed with adequate minuteness. Under the head of antiquarian topography and history are the British remains at Avebury, which are particularly described. Barrow is an entertaining, though not a very profound article. Bard is very superficial, and very erroneous: the writer quotes Mac Pherson's Ossian as true history. The most original and instructive article, however, in the whole volume, and which exhibits most decidedly the hand of a master, is basso-relievo. We have little hesitation in attributing this to the taste and science of Mr. Flaxman. After defining the term, the author proceeds to trace the history of this branch of art. Acquiescing with the writer of the article in the Encyclopedie, that basso-relievo owes its birth to figured or hieroglyphic writing, Mr. Flaxman proceeds to characterize the Egyptian bassorelievos as being the oldest:" in these the figure is sunk in such a manner that the surface of the ground forms an enclosure or outline whose greatest depth is equal to the greatest projection of the figure." "We find in the Egyptian figures, compounded of different animals, that each part is a copy of nature. In the human figure, the body and limbs were represented in general forms. The fi.c, as being the most interesting part of the person, was more minutely expressed. The form of the face was a rounded egg, lines of the eyebrows and the nose, the bottom of the nose and the lids, simple curves, inclining upwards from line of the mouth inclined upwards in the same direction with the eyes. The eyes were full, nearly on a level with the forehead and cheeks, and the lines of the eye-brows, lids, and borders of the lips, marked with precision. The chin appeared small and bony, the neck round, the shoulders high and broad, except the marking of the breast, little distinction of the muscular forms in any part of the body and limbs, the loins narrow, the limbs round, rather straight and slender, their joints slightly indicated, the hands and feet rather flat, the fingers and toes rounded, without the appearance of joints, and nearly of the same length." "The quadrupeds on Egyptian menuments are represented in profile, and in the simplest attitudes. The parts of which those are composed are fewer and more general than those in the human figure. This is one animals; the mechanical manner in which reason why the Egyptians excelled in the r the shoulder is drawn of the lion and sphynx (where they have displayed more anatomy than in any other part) presents a simple, but not just account of the structure of that member of the body: these observations apply to the state of sculpture before the time of Alexander the Great ; after which period, at partook of the improvements introduced by its Grecian conquerors." From the Egyptian the author preceeds to the Indian and Persian bassorelievos, and then enters upon an exa mination of those of Greece. The Greeks seem to have taken up the art nearly where the Egyptians left it, there being a very striking sirailarity between the earliest Greek basso-relievos and the best of the Egyptian ones. The Etruscan gems, as they are called, are shown with high probability to have been exe cuted by Greek artists. The style of the basso-relievos of Greece prior to the time of Pericles is then analysed, and illustrated by references to examples; from which we learn, first, their method of representing the gods; secondly, their manner of drawing the human figure and its actions; and, thirdly, the dis tinguishing characteristics of the dra peries, &c. The age of Phidias then passes in review, as far as concerns the exquisite basso-relievos which were executed by the hands or under the direc tion of this great master, and which even now, in the mutilated state to which they have been reduced by time and barbarian violence, are objects of despairing imitation to the best of our modern artists. "The execution of these works is equal to the conception; the sentiment is elevated and fit, the composition is noble, full, and various; the gods are sublime and beautiful, their positions present dignity and repose; the herocs are vigorous and active, and an admirable simplicity reigns through the whole; whether you are roused by the terrific engagement of a Centaur and a Lapitha, or captivated by the modesty of the virgin chorusses. In the battles, the figure is shewn in those elastic curves and varied movements, those uncommon but advantageous situations, which equally excite surprise and admiration; every part is intelligible; they occupy such spaces of the ground as leave sufficient blank to render the outline distinct; and their quantities are so distributed, that one part is not bare while another is crowded; the lines themselves also become an ornament. The stories are told by one plan or ground of figures; and, like the principal characters in the tragedies of Aschylus, Euripides, and Sophocles, their effect is weakened by no under-plot of inferior heroes. The drawing of the figures is of the finest style, the outline and forms are chosen, the greater parts boldly expressed, the lesser parts delicately indicated, but not more than necessary " The account of the basso-relievos of Italy is introduced by the sculptured tomb supposed by D'Ankarville to be that of Tarquin the elder: the triumphal arches and columns, and sarcophagi, are then noticed, and the gradual decline of the art till the age of Constantine. The revival of this branch of sculpture is dated from the year 1065, when the cathedral at Pisa began to be built. The works of Nicolo Pisano and his scholars in the thirteenth century are mentioned with merited praise; and the gate of the baptistery of St. John in Florence, of which Michael Angelo said that it deserved to be the gate of Paradise. Mr. Flaxman then shows that the Christian religion presents personages and subjects equally favourable to sculpture as are to be found in the ancient classics, suggests some very judicious hints on the choice of subjects, and the manner of treating them, and concludes this very interesting article with an enumeration of the finest antique bassorelievos which are to be found in the cabinets of England. The volume before us is further enriched with two architectural articles of merit, namely, basilica and baths; and with a long account of banks, and the bank of England in particular. The last article is battalion, which is treated of with all the minuteness of the regulation book, as if it was drawn up by some volunteer officer for the use of his parish association. CHAPTER XIX. EXPERIMENTAL PHILOSOPHY. THE second volume of M. Klaproth's Analytical Essays is by far the most in portant of the contents of the present chapter: it is a mine of highly valuable facts, to which the practical chemist will recur again and again with undiminished satisfaction. M. Tingry's Treatise on Varnishes will be found to be a useful and well arranged collection of information, relative to all the branches of this beau tiful and important art. Mr. Howard's Treatise on the Modifications of Clouds is very creditable to the author, as opening a scientific road to a department of meteorology that has hitherto been, for the most part, abandoned to the casual observation of the vulgar. The Researches into the Laws of Affinity by M. Ber thollet, and the Chemical Statics of the same author, will no doubt be received by the public with all the deference which is due to so judicious and acute a philoso pher. Mr. Leslie's interesting work on heat ought also to grace the present chapter, but we are unavoidably obliged to postpone it to our next volume. ART. I. Analytical Essays towards promoting the Chemical Knowledge of Mineral Substances. By MARTIN HENRY KLAPROTH. Vol. II. Translated from the German, 8vo. pp. 267. THE name of Klaproth ranks among the very first of practical chemists, and the sciences of chemistry and mineralogy are under unspeakable obligations to him, not only for the accurate analyses that he has made, and the new substances which he has discovered, but for the precision which he has introduced into the art of analysis itself, by the application of new menstrua, by improved methods of using the old ones, and especially by the establishment of the fundamental rule that no substance can be reckoned to be properly analysed, till every portion of it has been brought into solution. The former volume of these masterly essays was published some years ago, and the present will, we doubt not, be received by the chemists of England with the same satisfaction as its prede cessor. The first essay, entitled an examination of the auriferous ores of Transylvania, is uncommonly valuable. The substances here analysed are the aurum problematicum, aurum graphicum, yel low auriferous ore, and foliated anriferous ore. Besides the gold, lead, silver, and copper which had been already ob served, the presence of another metallic substance was indicated, which was by some supposed to be antimony, by others bismuth. The celebrated Bergman, from the results of his own experiments, suspected that the first of these ores, which was the only one which he exa mined, contained a new metal. The ores themselves are very rare, and it was probable that the precise nature of their contents would long remain in uncer tainty; but fortunately a sufficient quantity was put in M. Klaproth's hands to enable him to undertake a minute exa mination of these obscure minerals. The result of his inquiries is the disc very of a new metal, called by him tel lurium, and which forms 92.5 per cent. of the aurum problematicum: the leading properties of this new metal were also ascertained by M. Klaproth, and are recorded in this essay. The next article of considerable im Portance is the analysis of the newly discovered mineral called gadolinite. This had already been examined by professor Gadólin, who had detected in it a new earth, called ytria, from Yterby in Sweden, whence the mineral is procured. By the experiments which are described in the present essay, the analyses of Gadolin and Ekeberg are confirmed and corrected, and the claim of ytria to the character of a peculiar earth is fully substantiated. The analysis of the saline deposit of the hot spring, at Sasso in Sienna, (hence called by the name of Sassolin) will be read with interest, on account of the unusual result of boracic acid, in the proportion of 86 per cent. which it afforded. In the mellilite or honigstein, M. Klaproth has discovered a new acid not very different from the benzoic combined with alumine. The 85th essay is devoted to an examination of umber, a substance of great use to painters, and concerning the nature of which, there has been much difference among chemists, some considering it as vegetable matter in an advanced state of decomposition, and others regarding it as a colorific earth, analogous to yellow earth. That which was made use of in the present analysis came from the island of Cyprus, and consists of the oxyds of iron and manganese, mixed with a small proportion of silex and alumine. The muriated lead of Derbyshire, an extremely rare mineral, and the only substance in which muriatic acid is found combined with this metal, is the subject of the 86th essay this, together with the two succeeding essays on the native phosphats and sulphats of lead, will be greatly esteemed by the metallurgical · chemist. In the 96th essay a new species of copper, the native phosphat from Firneberg, which had been erroneously ranked among the malachites by Nose and Karsten, is described and analysed. The examination of kryolite, a new mineral lately brought from Greenland, is peculiarly interesting, as it turns out to be a new salt, composed of fluoric acid, soda, and alumine. In this the proportion of pure dried soda is no less than 36 per cent. The presence of fixed alkali, as an essential constituent of some of the hard fossils, was, we believe, first ascertained by Klaproth in his analysis of leucite; he found it to contain 20 per cent. of potash; Dr. Kennedy then discovered soda in the lavas of Etna, and in some of the Scottish basalts; Vauquelin detected potash in compact felspar; and from the vo lume now before us we perceive that the persevering sagacity of the author has found both soda and potash in several other minerals, a discovery of no small importance in geology, and which perhaps may be found advantageous in an economical point of view. The klingstein, a variety of hornstone porphyry, a substance of which many mountainous tracts are almost entirely composed, contains more than eight per cent. of dry soda; the pitchstone of Meisen also contains a small portion of the same alkali; the pumice yielded on analysis 3 per cent. of a mixture of soda and potash; and in the pearlstone, a new mineral from Hungary, M. Klaproth found 4 per cent. of potash. The former volume of this valuable work is of unspeakable use to the practical chemist, as illustrating the efficacy and mode of employing the most powerful agents of chemical analysis, and in ascertaining, with extreme accuracy, the constituent parts of metallic and other precipitates, from which the results of analyses are generally calculated. The mode of sub. duing the gems and other refractory minerals, by means of caustic alkali, was invented and brought to perfection by Klaproth, and many examples of its application occur in the former part of these essays. Nor will the volume before us be deemed of less importance in this respect: the careful reader will observe that the author has made some addition to his list of reagents, and has discarded others, the action of which was not sufficiently precise: some of the most important of these we shall proceed to point out. The application of the succinats of soda and ammonia, in separating iron from manganese, will be found in the essays on gadolinite and umber; but this method does not appear to be much superior to the old one, which we find still retained by Klaproth, page 250, and which, with proper care, is certainly capable of effecting a very accurate separation of these metals. Of the use of carbonated potash, and nitrated barytes, in decomposing the metallic sulphats, a good example occurs in the essay on the sulphats of lead. As a precipitate for arsenic, M. Klaproth now uses acetat of lead, instead of the less accurate mode of proceeding made use of in his former volume. In ascertaining the quantities of copper and lead in a mineral, M. Klaproth still prefers his old method of precipitating them in their metallic state by iron and zinc, to the method adopted by Mr. Hatchet, of converting the copper to brown oxyd, and the lead to sulphat. The most original and important agent, however, which chemistry will derive from the present volume, is barytes, as a substitute in certain cases for caustic alkali. Those refractory minerals which contain soda or potash, and sometimes both together, cannot be very conveniently brought to a soluble state by means of the alkalis, without throwing some uncertainty on the alkaline contents of the mineral itself; whereas, by making use of barytes, all the gool effects of potash are obtained without its ambiguity. The method is to mix the pulverized mineral with nitrated barytes, and by exposing the mass to a red heat, to drive off the acid, and thus overcome the refractoriness of the mineral by the action of the barytes; the whole being then taken up by nitric or muriatic acid, the barytes is completely separated by sulphuric acid. As this work is not likely to be consulted, except on account of the valuable facts which it contains, the translator will be considered as having performed the most essential part of his duty if he has guarded against ambiguity and er ror. We have no fault to find with him on this head, and can therefore readily forgive the numerous idiomatical mis takes, which clearly show that German is his native language. ART. II. Elements of Galvanism, in Theory and Practice; with a comprehensive View of its History, from the first Experiments of Galvani to the present Time; containing also, Practical Directions for Constructing the Galvanic Apparatus, and plain Systematic Instructions for Performing all the various Experiments. Illustrated with a great number of Copper-plates. By C. H. WILKINSON. 2 vols. 8vo. THE peculiar interest which was excited in all parts of Europe, by the phenomena of galvanism, naturally gave birth to a great variety of dissertations. Many of these contained little more than flimsy speculations, which are already consigned to a merited oblivion. Not a few, however, were enriched by valuable experiments and well digested hypothe ses, either immediately leading to some important discovery, or overthrowing conjectures which had been previously advanced. Many of these communications were presented to the public through the medium of periodical publications, or the transactions of learned societies, of course, scattered through different parts of Europe, and written in the native languages of their respective authors. It is therefore obvious, that a work of the nature of Mr. Wilkinson's, if well executed, must be materially serviceable to the interests of science, by collecting into one uniform series these scattered fragments, thus exhibiting the progress that has been made, and of course marking out the parts that require farther investigation. The value of such a work must obviously depend upon the diligence which has been exercised in the collection of materials, the judgment with which they are selected, the method in which they are arranged, and the perspicuity with which they are announced. The histo rical detail occupies the whole of the first and nearly half of the second volume; the remainder is occupied in the deve lopement of the peculiar theory which has been adopted by the author. The plan of the first part of the work is principally that of the chronological crder of the discoveries, though in some cases this has been violated, for the purpose of introducing a more systematic view of any particular branch of the subject. It would carry us too far beyond the limits prescribed to our undertaking, were we to attempt a complete analysis of the historical part of this work. We shall therefore only notice those points which appear to us peculiarly deserving of commendation or of censure, reserv. ing for a more close investigation the parts in which our author either supports opinions peculiar to himself, or contrary to those generally established. The first chapter is principally occupied with a detail of the original discoveries of Galvani, and the hypothesis which he formed to account for them. Although in the first instance he was in debted to accident, yet he manifested very considerable penetration and ability |