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AWL, or, as Dr Thomson overlooks falts, AW. The second genus is AS. The first species, Corundum, contains the oriental ruby and sapphire, correctly placed here according to M. Chenevix's analysis ; but, according to Mr Klaproth's, sapphire belongs to A, of the imperfect corundums; that from China, as well as Emery, belong to AIS, as the quantity of iron exceeds that of filica. The second species, Chrysoberyl, contains 6. of lime, and therefore belongs to ASL. The third, the Topaz, is right, as well as the Fibrolixe, also numbered the third by mistake, and the fourth Sommite. The third genus is A M. The first fpeeies, Spinel Ruby, belongs, by Vauquelin's analysis, to AMC, and by Klaproth's to ASM; and the second, the Ceylanite, to A I M. From these three first genera our readers will be able to judge of the others. In this edition, a chapter is added on compound minerals, translated from Brochant; and the last chap ter treats of the analysis of minerals.
The fourth book treats of Vegetables ; and the fifth, which concludes the work, of Animals. No part of the work has undergone so many alterations in this edition as the chapter which treats of the ingredients of vegetables. The author's ideas on the importance of this subject seem to have undergone a very great change, and to this change of opinion his readers are indebted for much very valuable information ; for, instead of 60 pages, it now occupies 160 ; although there is very little of it, except what is derived from his own experiments, which was not known to pharmaceutills when the former edition was pubLished. But vegetable chemistry has become fashionable, and Dr Thomson has applied to it with very great success, in his experiments on gum, sarcocol, and the bitter principle.
An appendix is added, containing those discoveries of importance which were made during the printing of the work; and we are sorry that we must conclude our analysis, by lamenting that the index is not more copious. . . - Dr Thomson has, in general, adopted M. Chenevix's nomenclature ; but we have occasionally observed deviations inconfiftent with it, as tannat and other ats for combinations of substances which are not acid. There, however, we believe to be accis dental.
Dr Thomson's method of distinguishing the degrees of oxidation in the metallic oxides, by prefixing the first syllable of the Greek ordinal numbers to the word oxide, as prot-oxide, deutoxide, &c., and the maximum of oxidation by per-oxide, we think is an improvement. On the other hand, we trust that our author's example will induce no one to follow him in distinguishing those metalline falts which contain the metal in the ftate of
per. per-oxide, by prefixing the particle oxy to the name of the acid, as that form of expression has already another much more natural meaning. • Capacity for caloric,' is also used by Dr Thomson to express the quantity of caloric in equal bulks of bodies, although it has hitherto always had a reference to equal weights. Our author seems also to have a very great dislike to superfluous letters, not only in the names of substances, but also in those of the German chemists; but hermitad, Humbolt, Westrum, &c. will appear to a German eye as awkwardly exotic as Tomson would do to our author's.
The references to authorities with which this work abounds, are extremely valuable ; and, in general, Dr Thomson gives a due degree of credit to the discoverers of particular facts; and if, in some instances, through ignorance or inadvertence, the real discoverer is not mentioned, in others his praise alınost amounts to flattery. For example, his gratitude to that excellent chemift Air Hatchett, for having communicated to him his unpublished experiinents on resins, has led him to exaggerate their importance to a degree that we conceive must be displeasing to that gentleman's modesty, especially as most of the facts, which Dr Thomson seizes every poílible opportunity of announcing as Mr Hatchett's discoveries, were previously known. His general statement is in the following words : « Hitherto it has been affirmed by all chemiits, ancient and modern, that the alkalies do not exert any action on resins. Fourcroy, for instance, in his last work, affirms this in the most positive manner; but the experiments of Mr Hatchett have demonstrated this opinion to be completely erroneous.' And after stating the experiments, he proceeds, · Nothing can afford a more striking proof, than this, of the necessity of repeating the experiments of our predecessors before we put implicit confidence in their affertions. The wellknown fact, that the soap-makers in this country constantly mix sofin with their soap ; that it owes its yellow colour, its odour, and its easy folubility in water to this addition, (?) ought to have led chemiits to have suspected the folubility of resins in the alkalies. No such consequence, however, was drawn from this notorious fact.' In opposition to all this, we thall quote only one modern chemist, Gren, who expressly says that 'the refins also torm, with the caustic alkalies, soapy combinations.' Again, 'It lias been supposed also,' says Dr Thomson, ' that the acids are incapable of acting upon the resins; Fourcroy is equally positive with regard to this; and Gren speaks of it in such a manner that every reader must conclude that he had tried the effect of nitric acid upon resins. Yet Mr Hatchett has ascertained this fpirion likewise to be erroneous, at least as far as nitric acid is
concerned.' The following is the manner in which Gren speaks of it: .. Concentrated nitric acid acis upon porudered roin every powerfully, and nitrous gas is evolved; but the running together of the rosin into lumps, makes its complete solution in nitric acid extremely difficult.'
To his predecessors in the laborious task of compilation, Dr • Thomson feldom makes any acknowledgment, although we think it would have been but just, to have mentioned in the preface his obligations to them, especially to Fourcroy, from whom he has often borrowed largely. In some instances,' an author of this description is quoted for a particular fact, although the whole paffage be borrowed from him. A very flagrant example of this kind occurs in vol. IV. p. 129, when Brochant is quoted in such a manner as to make it appear that nothing but the enumeration of Werner's classes is taken from him, whereas the whole chapter, Of compound minerals, extending to twenty-five pages, is an abridged translation of Brochant, with the addition of three alla. lyses by Dr Kennedy and M. Klaproth, and one observation by the author.
Upon the whole, notwithstanding the numerous errors which we have discovered, or believe we have discovered, in this work; they are much more than counterbalanced by its general merita. The immenie quantity of chemical information which it contains, is highly creditable both to the abilities and the industry of the author, and if, in a future edition, he will restrain a little his propensity to premature generalization, and free his numerical expressions from the numberless errors which now render it imrolible to trust to any of his calculations with security, we have no doubt that it will continue to maintain its reputation as the beit repository of chemical knowledge that has yet been oifered 10 :he public.
If any of our readers should be inclined to object, that ile general tone of the preceding obfervations dues not accord very harmoniously with this concluding culogium, or to accuse 11s wi having specitied little more than the defcets of a work of such uquestionable inerii, we would beg leave to remind then, thut Dr Thomson is neither humble nor obscure crough to find in need of reconncndation or encouragement from us. The public has already done ampie justice to his talents; and he is himself perfectly aware of the extent of his claims on their favour. In this situation, while it is almost unneceflary to proclaim his merits, it becomes of the greatest consequence to point out his mistahes and inperfections. Under the sanction of so great an authority, cirors are prop.zgate with a very mischievous rapidity, and the author himlelf is apt to become presumptuous and precipitate, W e no one is to be found wo will admonish lum of his failures
and faults. Notwithstanding the freedom of our remarks, we doub: if any of Dr Thomson's readers have a higher sense than we huve of the value of this publication; the perufal of which we very earnestly recommend to every student of chemiitry.
Art. X. Specimens of the Early Englis Poels : To which is pre. fixed, An Hiflorical Sketch of the Rise and Progress of the En lilis Portry and Language". By George Ellis Esq. The Third Edition, Correétud. 3 vol. 8v0. The first edition of this interesting work appeared in 1790, 1 compriêng in one volume many of the most beautiful small poems which had appeared during the sixteenth and seventeenth centuries. The pian wis certainly worthy of being enlarged ; and accordingly, in the second edition, published about a year ago, and rapidly disposed of, as well as in that which is now beiure us, it has received such considerable additions, that the work has increased to chrice the original size; and Mr Ellis has established his claim to the character of an original author, as well as to that of a judicious collector and extitor of the forgotten poems of antiquity. The first volume contains the preliminary historical sketch of the rise and progress of English poetry and language; the second and third are occupied by those specimens which give name to the whole. We thall endeavour succeslively to analyse the contents, and examine the merits, of these two divisions of the work.
It is obvious to every one who has studied our language, whether in prose or poetry, that a luminous history of its rise and progress muft neceffarily involve more curious topics of discussion than a similar work upon any other European language. This opinion has not its fource in national partiality, but is dictated by the very peculiar circumstances under which the English language was formed. The other European tongues, such at least as have been adapted to the purposes of literature *, may be divided in. to two grand classes-those which are derived from the Teutonic, and those which are formed upon the Latin. In the former class, we find the German, the Norse, the Swedish, the Danish, and the Low-Dutch, all of which, in words and construction, are dialects of the Teutonick, and preserve the general character K4
• We do not mention the dialects founded on the Celtic and Sla. vonic languages, because they have not been used in literary compofi. tion ; nevertheless, the same observation applies to them as to the others ; they have each their derivation from a fingle mother-root, and Le poi, like the English, a compounded or mingled language.
is the links original thanclass and upo
of their common fource, although enriched and improved ty terms of art or of science adopted from the learned languages, or from those of other kingdoms of civilized Europe. The second class comprehends the Italian, the Spanish, and the French in all its branches. It is true, the last of these has, in modern times, owing to the number of French writers in every class and upon every subject, departed farther from its original than the two others; but still the ground-work is the Latin ; and the more nearly any specimen approaches to it, it may be safely concluded to be the more me cient; for, in truth, we know no other rule for ascertaining the antiquity of any particular piece in the Romanz language, than by its greater or lighter resemblance to the speech of the ancient Romans, from which it derives its name. Thus every language of civilized Europe is formed of a uniform pattern and texture, either upon the Teutonick, or upon the Latin. But the faire chance which has peopled Britain with such a variety of tribes and nations, that we are at a loss to conceive how they should have met upon the same spot-and that, comparatively, a small one-has decreed that the language of Locke and of Shaker speare should claim no peculiar affinity to either of thele grand sources of European speech ; and that if, on the one hand, its conformation and construction be founded on a dialect of the Teutonick, the greater nunber of its yocables should, on the other, be derived from the Romanz, or corrupted Latin of the Normans. It is interesting to observe how long these languages, uncongenial in themselves, and derived from sources widely different, continued to exist separately, and to be spoken respectively by the Anglo-Norman conquerors and the vanquishied Anglo-Saxons. It is still more interesling to observe how, after having long flowed each in its separate channel, they at length united and formed a middle dialect, which, though employed at first for the mere purpose of convenience and mutual intercourse betwixt the two nations, at lergth superseded the individual speech of both, and became the apt record of poetry and of philosophy,
The history of poetry is intimately connected with that of language. Authors in the infancy of composition, like Pope in that of life, may be said to lisp in pumbers.' Hiftory, religion, morality, whatever tends to agitate or to footh the passions, is, during the ealier stages of society, celebrated in verse. This may be partly owing to the ease with which poetry is retained upon the memory, in those ruder ages, when written monuments, if they at all exist, are not calculated to promote general information, and it may be partly owing to that innate love of song, and sensibility to the charins of flowing numbers, which is distinguishable even among the most favage people. But, what