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praise of considerable ingenuity in the application of a wellknown theory, and this is all. But it is equally true that he was not above accepting from those by whom he was surrounded, and who, for the most part, were much inferior to himself in knowledge, the character of the inventor of a perfectly new philosophy in grammar, superseding and annihilating all former systems. This exalted station in the intellectual world he certainly arrogates to himself in many parts of his work, and his vanity has been 'fed by the ignorant wonder of those who have never studied grammar, but in the Diversions of Purley. Flatulent with the fumes of this hyperbolical praise, he begins at last to assume the style of an oracle, and not content with carrying through the work the air of a great exposer of prescriptive errors, and a revealer of new truths to mankind, the hierophant suddenly and abruptly concludes his work with a sort of mysterious hint to his disciples, that all which they had hitherto heard was only the prelude to some grand explosive discoveries which would at once blow up all the systems of logic and metaphysics by which the world had been grossly deluded. In what may have been the expectation of Sir Francis and his other disciples, we do not pretend to know, but, for ourselves, we cannot but suspect that the true reason of Mr. Tooke's denying all further communication to his pupil, either respecting the nature of the verb, or the wonderful things he professed to have in reserve, was, that he had come to a dead stand, and had, in good truth, nothing more to communicate.

Of the private character and qualities of the late Mr. Tooke we have forborn to say much, for the reasons given in the beginning of this article. We have never sat at any of his Sunday dinners, or witnessed the style of his manners and behaviour. We have heard that his temper, if not mild, was cool, and that all that was done by him, whether good or bad, was considerately done; that in strength of nerve no man was his superior, and we have seen that, in his steady adherence to his purpose, all his words and actions proclaimed his consistency and courage. No moral or physical evils (and he seems to have had a share of both) were capable, according to report, of making any impression upon this characteristic fortitude; and, what is much to the honour of his philosophy, amidst the sufferings of his latter years, his friends appear to have found in him neither the querulousness of disease, nor the moroseness of

age. We have heard him praised for his hospitality to his friends, and his wit is said to have run sparkling and clear to the very dregs. We have understood that in conversation he was instructive, fluent, and full of anecdote, but at the same time

VOL. IV. NO. VII.

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lax, disputatious, and dictatorial, and too ready to sacrifice the most important questions to the vanity of paradox. Of his general intellectual powers too much has been said. His mind seemed to have been deficient in compass and comprehension, as much as it excelled in subtlety, force, and penetration. Subtlety and force in conversation frequently stand for merit of a higher kind. But the Diversions of Purley have shewn him in his true light, as a man made for minute investigation, for single efforts, and for desultory research, but wanting in that vigorous intensity of thought which is necessary to the thorough prosecution of a complicated theme, from its first principles to its distant analogies; and in that philosophical taste which, disposing the parts of a subject in their natural order, facilitates the intelligence of the reader, and dismisses him permanently impressed.

His social hours were chiefly passed among men of abilities inferior, but of sentiments correspondent, to his own, and among whom, as he could not meet with much opposition, it is probable he displayed no want of complacency. But to those from whom he differed, either in literature or politics, he was not, as we have seen, remarkable for his forbearance or charity. Against dignities and authorities, and against all those situations of honour and trust, to which good men for the sake of society pay a cheerful reverence, his life was one unceasing warfare. This we have heard sometimes imputed to the provocations of perpetual failure in his attempts to raise himself to an eminence on a level with his talents, and we are ready to admit this excuse as far as envy can be an excuse for acrimony, or disappointment for revenge. It may be, as we have found it suggested in a delineation of the character of Mr. Tooke lately in our hands, that had he obtained a situation in which his great talents had found their proper scope and exercise, that disposition and conduct which, under the exasperations of disappointment, were dangerous to the peace of society, would have been the source of blessings to the nation. We will not contradict this charitable surmise, but we must be permitted to say that we can never regret, that the man on whom disappointment operated in the manner supposed, was never tried in a situation of power, or trusted with the accomplishment of his wishes.

Art. II.Elements of Chemical Philosophy. By Sir Humphry

Davy, LL.D. Secretary to the Royal Society. Part I. v. i.

Johnson, St. Paul's Church-yard. Price 18s. WE opened this work with great expectation; we have not been disappointed. It is the work of a man whose discoveries have formed an era in chemistry,—who has studied the science not merely in books, but in the operations of the laboratory, and in the phenomena of nature; and who has been for many years accustomed to deliver popular illustrations of it. No person has better qualifications for a work upon the elements of chemical philosophy; and we bestow no mean praise when we say, that we think he has executed the task in a manner worthy of himself,

The materials, and the arrangement of the materials, are equally new. Respecting the former we shall speak last, as we have most to say upon it. The arrangement is simple and clear, and the parts well connected. An elegant, learned, and concise history of chemistry forms the introduction. It is the first which has appeared, that is not a copy of Bergmann's. Sir H. Davy has not, like the Swedish chemist, gone into remote antiquity in search of the origin of chemistry;--to Cain and Tubal-cain, ---but has shewn that chemistry was not even known to the Greeks; that it's birth-place was the furnace of the alchemist, and that its native country was Arabia. He has brought down his historical sketch to the present time, and thus traced the progress of chemistry from an art to a science. The present volume constitutes only the first part of the whole work, but it is all that has yet appeared. The subjects treated are,“ the laws of chemical changes, and the undecompounded bodies, with their primary combinations." The first division of the work relates to the powers of matter in general; the second, to radiant or ethereal matter, as heat, light, electricity, and magnetism; the third, to empyreal undecompounded substances, viz. oxygen and chlorine, and their combinations with each other; the fourth, to the undecompounded inflammable substances not metallic, and their combinations with the preceding bodies and with each other; the fifth, to the metals and their primary combinations; the sixth, to sub tances the nature of which is not fully known, and the seveuth and last, to the analogies between the undecar pounded substances, speculations respecting their nature, and the relations of their compounds. This arrangement in the present state of our knowledge is excellent particularly as it separates the certain from the doubtful, the known from the unknowır, the established truths of science and

generalizations of facts, from speculative views and analogical reasonings.

It is not our intention to enter into a minute analysis of this work, but to consider the striking features which give it character, and the new and general doctrines which it contains.

When we compare what chemistry is at present with what it was fifty years ago, we are filled with astonishment. The German philosophy was then the fashion of the times, and the German school was at the height of its glory. A few substances only were known, and those very vaguely; the number of the ancient metals was indeed somewhat enlarged, but the chemists of those days had not learnt to distinguish the different kinds of earths, and they were not at all acquainted with the different kinds of gasses. They called all the airs they met with factitious airs, and conceived them to be all merely different modifications of the air of the atmosphere. Statics had not been brought into the laboratory. The great agent was fire; and the “philosophers by fire” let the gasses or spirits, as they were called, escape in their experiments, and rejected the fixed residue, the “ caput mortuum” as useless. By means of a few elements borrowed jointly from the Greeks and the alchemists, with the assistance of their main spring phlogiston, they were able to explain in a manner satisfactory to themselves all the changes in art, and all the grand operations in nature,—and they were contented. Such nearly was the state of the science when Dr. Black discovered the existence of carbonic acid gas; a discovery which may be truly said to have given wings to chemistry. It at once demonstrated that prevalent opinion to be erroneous which supposed the existence of only one species of elastic fluid, and rendered it more than probable, that what had been neglected under the title of factitious airs, were distinct and peculiar gasses. The light which from this one discovery burst upon all departments of chemistry, roused the zeal of enquirers in this country to the investigation of gaseous bodies, and their labours were rewarded with the most brilliant success. Cavendish, by the discovery of hydrogene, and of the composition of water and nitric acid, and Priestley, by the discovery of nitrous gas, nitrous oxide, and the composition of the atmosphere, obtained, as it were, the keys of nature's laboratory. Black, Cavendish, Priestley, were the founders of pneumaticchemistry, and may with propriety even be called the founders of the science of chemistry; inasmuch as these active investigators, and preeminently among them Mr. Cavendish, first introduced weights and measures, and applied them for the establishment of chemical truth. The developement of the doctrines of latent heat by Black, the analytic labours of Scheele and Bergmann, and the generalization of facts by Lavoisier, constituted the first stage of modern chemistry.

Let us pause a moment to consider the charrcter of the lastmentioned philosopher, who formed a party and a school, and left a proud name behind him in this department of science. The merit of Lavoisier was that of a sound logician, not of a discoverer. He was strongly impressed with the importance of keeping the imagination under the discipline of experiment; that nothing must be taken for granted, nothing admitted to exist that is not made evident to the senses; that occult causes, and unknown bodies, and all the remains of scholastic trifling and alchemical mysticism should be banished from the new philosophy; that truth was to be reached by the road of induction, and that scientific principles must be acquired from the comparison and expansion of individual facts. To make one proposition of the whole, that all bodies are to be considered as simple substances, which have not yet been decompounded. The defective part of his great design was the French nomenclature, which, though admirably adapted to a perfect science, was not at all suited to one in its intancy. It was a tight garment that did not admit of enlargement, well fitted to the man, but very unfavourable to the

growing child.

After the discovery of the Leyden phial, in 1746, electricity became a subject both of popular and scientific attention. It was next to a miracle that an invisible power of such an extraordinary nature, as to be capable of melting the hardest metals, producing all the phenomena of light and fire, and destroying even animal life itself, should be confinable in a glass vessel, and subject to be arrested in its progress by silk. Neither was the interest in electricity diminished by the labours of Franklin, who identified it with the lightning of heaven, and by the simplest means, by a school-boy's kite, realised the fable of antiquity respecting the Promethean theft. In the progress of enquiry, fresh wonders were added to electricity. The lightning of the thunder-storm was found to be wielded by some of the inhabitants of the deep: the gymnotus, the silurus, the torpedo, were proved to be armed with this power, and capable of voluntarily employing it as a weapon of attack or defence. But still electricity was uuconnected with chemistry, and remained an insulated science, being analogous to nothing but magnetism.

In 1800, the first step was taken to connect the two sciences by the great discovery of the pile of Volta. This instrument,

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