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to three proportions of phosphorus to form three of phosphoric acid, and the four proportions of hydrogene combine with one of phosphorus to form one proportion of hydro-phosphoric gas, and there are no other products. This relation of proportions might be illustrated in a thousand ways, particularly by the decomposition of metallic salts by metals, and of earthy salts by alkalies ; --in the former, when the salts are neutral, there is merely an exchange of metals, the one taking the place of the other, without any change whatever in the combined proportions of oxygene and acid: so that M. Gay Lussac's law respecting these neutral metallic salts is perfectly correct,--that the acid is proportionable to the oxygene, and that the one being known, the quantity of the other may be calculated.

This doctrine, in its present extended form, is of very recent origin.' When chemistry began to be cultivated as a science, all those who investigated the subject of affinities, seemed satisfied that bodies were capable of combining only in certain determinate proportions, but their views were not at all definite, and apparently rather the result of general speculations on the nature of attraction than induction from facts. Mr. Higgins was the first who descended to particulars, and embracing the corpuscular philosophy, attempted to prove that bodies combine particle to particle, and of course in definite quantities. Thus he considered water a binary compound of one particle of hydrogene and one of oxygene, and sulphureous acid gas as a similar compound of one of sulphur and one of oxygene, whilst he supposed sulphuric acid to be a ternary compound of one particle of sulphur and two of oxygene. But Mr. Higgins views were very much neglected till the attention of the learned were directed to them by Sir H. Davy; and Mr. Dalton had all the merit of being the original founder of this doctrine.

Mr. Dalton is certainly deserving of great praise for what he has done. He revived the theory when it was entirely forgotten, and supported it with much ability ; extending its empire, and shewing its agreement with a great number of facts. Of all the authors who have written on it, Sir H. Davy, in the present work, has taken the most comprehensive view of the subject, and introduced by means of his original researches the greatest harmony into all its parts. And he, too, has the merit of separating it from the corpuscular philosophy, and of making facts its only foundation. Mr. Dalton, on the contrary, appears to be a fond disciple of Leucippus and Democritus, who above 2000 years ago taught that all things were composed of immutable atoms. This philosopher not only believes in the existence of atoms, but even imagines himself acquainted with their invisible forms,

and conceives himself capable of calculating their relative weights and their number in any given volume of elastic fluid. Admitting his premises, his conclusions we will allow are capable of demonstration, but the existence of atoms, and even of matter itself, must be takeu for granted, and does not admit of rigorous proof. We therefore consider the science as much indebted to Sir H. Davy for having divested this important theory entirely of its hypothetical dress, and placed it before the eyes of his readers in its

proper

attitude. Nothing can shew to greater advantage the benefits of the theory of definite proportions than the work before us. Every where there is the greatest precision; the compositions of bodies are rigorously ascertained and compared together; no ingredient is overlooked as insignificant; water in particular, hitherto so much neglected, has received a due attention, as forming a part of the character of the compound. The proportions of the constituent parts of bodies are represented by numbers, and the memory is but little burthened with retaining them, as each simple substance has always the same numerical representative. Thus 15 is the general symbol of oxygene, and 26 of nitrogene, so that when the proportions are known in which they combine together, the weights of the constituent parts are most readily found.

The late progress of this theory has been surprisingly rapid. It now embraces all the substances we are accurately acquainted with. The numbers representing oxygene and chlorine, hydrogene, sulphur, phosphorus, and carbon, and most of the metals, have been determined, and the proportions in which all these substances combine respectively with each other, is in a great measure ascertained. So that chemistry is now become almost a numerical science, and its operations admit of being reduced to numerical exactness.

The refutation which the author has given of Berthollet's doctrines appears to us to be completely satisfactory. He has repeated some of his experiments and found them incorrect; others he has explained on more simple principles; and Paff has proved in some of the particular instances adduced by the French chemist himself, that quantity or mass has no influence in modifying the results, or of enabling weak to overcome powerful attractions. We must confess that this refutation affords us no little pleasure, as Berthollet's views had not the simplicity of truth to recommend them, and their tendency was to create confusion, and to render chemistry an art rather than a science. “If chemical attraction," observes Sir H. Davy, “ be regarded as capricious in its effects, and as tending constantly

VOL. IV, NO. VII.

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to produce, different arrangements, chemistry is left without a guide, without any certain combinations, and no results of analysis can be perfectly alike: but fortunately for the progress of science this is not the case: the changes of the terrestrial cycle of events, like the arrangement of the heavens and the system of the planetary motions, are characterized by uniformity and simplicity; weight and measure can be applied to them, their order perceived and their laws discovered.”

We cannot in conclusion deny ourselves the satisfaction of transcribing the following extract, as a specimen of the ruling impressions which the ardent and successful pursuit of science has left upon the mind of Sir Humphry Davy." It is.contrary to the usual order of things, that events so harmonious as those of the system of the earth, should depend upon such diversified agents, as are supposed to exist in our artificial arrangements : and there is reason to anticipate a great reduction in the number of the undecompounded bodies, and to expect that the analogies of nature will be found conformable to the refined operations of art. The more the phenomena of the universe are studied, the more distinct their connection appears, the more simple their causes, the more magnificent their design, and the more wonderful the wisdom and power of their AUTHOR.

We have little doubt that these solemn views of the grandeur and simplicity of the works of God have been useful to Sir H. Davy in the regulation of his scientific pursuits, and have given ą zest to every object. Nor can we withhold from him the tribute of our thanks, for his virtuous, and we hope successful endeavours in all his public addresses on his favourite science, to impress on the minds of his pupils those sentiments which have afforded to himself so much pleasure and advantage.

In all his illustrations and analogies, (and even his manners have received a tincture from the ruling impressions of his mind,) he seems constantly to bear in recollection the humble and beautiful exclamations of the Psalmist: “The heavens are thine; the earth also is thine ; as for the world and the fulness thereof, thou hast founded them. The north and the south thou hast created them; Tabor and Hermon shall rejoice in thy name.”

ART. III.-Tales. By the Rev. Geo. Crabbe, LL. B. London.

Printed for J. Hatchard. 1812. To strike out a new path of interest or entertainment, either in poetry or prose, is become a task of some difficulty in this advanced

age

of literary competition. And it is no wonder if the struggle after novelty, where novelty is so hard to be found, should produce some anomalies in composition which rest their merit principally on their departure from long-existing practice. To this ambition of doing something not yet achieved, we are perhaps to attribute that rhythmetical prose which, but a short time ago, was a prevailing fashion, and from a similar cause we may perhaps deduce a late practice of writing poetry in the style and language of prose.

We are well aware that we are to look for the sublimest and most affecting passages of our greatest poets among those in which there is the least appearance of studied ornament, and the most unambitious use of language. The words in the passages to which we allude are usually taken warm and breathing from the intercourse of common life; but a reader of delicate ear and correct judgment soon becomes sensible that a certain secret in the arrangement and application of these homely words imparts to them, under the magical controul of these great masters, an effect not to be produced by the most shining assemblage of magnificent terms. For examples in proof of the propriety of this observation, we may refer generally to Shakspeare and Milton.

But whatever may be the grace arising from a skilful combination of single words of low origin, the same poetical result is not to be produced by the adoption of the phraseology and idiom of vulgar life. Cowper descended lower than any bard had done before him, and it must be confessed that it required a general excellence like his to atone for the wilful negligences of his style in many parts. General excellence has a tendency to consecrate occasional faults; and Cowper's defects, like the scanty vest and rugged manners of Cato, have, insensibly per haps, been an object of imitation to those who have had but little taste for his perfections. It is but justice, however, to this exquisite poet, and best of moral satirists, to remark, that he has, in numberless instances, produced, from the same sort of materials with which the plastic powers of Shakspeare and Milton wrought so successfully, the same surprizing fabrics.

But besides this beautiful application of ordinary terms, there is, it must be admitted, an ease, sporting on the very margin of negligence, which is very captivating in poetic composition, when its subject is the display of the manners or events of common-life. But it fares with this ease in composition, as it fares with what is usually called ease in behaviour: one is apt to suppose it consists merely in negation, and that to be graceful without the appearance of study, nothing is required but the absence of study. The supposition is natural, but very erroneous.

Ease is, in truth, the consummation of art, and the last refinement of labour. It is not a blank, or meagre outline, but may be compared to a mellow assortment of colours, which gives repose to the eye, propagating its pleasing effects, and making all around it partake of its character. Componit furtim subsequiturque decor."

Among the various departments of writing, there are none either in prose or poetry to which true ease is more becoming than tales, such as those in which Gower, Chaucer, and Boccaccio, have given us the picture of their own times. But in the ease which is so necessary to this species of writing, consists, if we mistake not, the difficulty of its execution, and the reason of the rarity of these productions since the age of the three contemporary geniuses to whom we have alluded. Such, indeed, is the merit of this arduous ease in the execution of the task of agreeable story-telling, that on this principally is founded the lofty reputation of Dryden, Swift, Prior, and Gay, Fontaine, Cervantes, and Marmontel; little else of their tales being their own except the manner of telling them. We might name, indeed, some females of modern times who are equally original both in the matter and manner, and whose matter and manner are worthy of Chaucer and Boccaccio, without being unworthy of the delicacy of their own feminine character. A little attention, however, to the structure of these compositions, will convince us that for the most part they have cost their respective writers no small degree of pains and assiduity. It is a most mistaken supposition which imputes the natural flow, and graceful simplicity, by which the style of many of these writers is often characterized, to carelessness or accident. They were most of them laborious writers; and those among them who have exercised themselves in various departnients of literature, have bestowed upon the fabrication of tales more than their ordinary care. We do not mean by care that strain and effort with which a dull man, or one who has no natural vocation to the thing, heavily accomplishes his task, but the solicitude with which a writer, having a clear impression of what constitutes the perfection of his work, and conscions of his danger of being carried into excess by the very strength of this impression, weighs and examines the products of his genius.

If these remarks are just (and we are afraid of their being

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