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look back into the history of this science, any farther than to the period which that nation claims as its own.

The modern theory of chemistry is founded upon a greater number of new discoveries than ever were made in a like space of time, or than ever had contributed to create a system of science; and, what is more extraordinary, those discoveries consist, not merely in facts, but in substances. More than a century before it was established however, many, both of the one and of the other, had been perceived; but they lay like heaps of ore upon the surface of the ground, visible to all their value quite unseen. In the oldest times of chemistry, since the revival of letters, airs of different natures had been perceived by Van Helmont, Rey, Boyle, Hooker, Hales, Moyou, Scheele, Priestley, and others, before any of the conclusions now admitted were drawn respecting them. And many things then known to our great countrymen, but neglected by the age in which they lived, might be held as happy anticipations of the modern theory.

The person who took up the science in this state, and began to new-model it, was Dr Black. In his investigation of the aerial fluids, he discovered one fact, the existence of carbonic acid; and one great point of theory, latent heat. Mr Cavendish, by far the most completely minded of all modern chemists, made known another aerial fluid, hydrogen; and ascertained the composition and nature of nitric acid. “In looking • for one thing, I have generally found another,' said Dr Priestley of himself; and to enumerate the discoveries of Dr

P.' said Mr Kirwan, would be to enter into a detail of most • that have been made within the last fifteen years'- discoveries ( which have new-modelled that science, and drawn to it, and

to this country, the attention of all Europe. It is certain • that, since the year 1773, the eyes and regards of all the

learned bodies of Europe, have been directed to this country 6 by his means.' By these three great men, a much nobler scientific junto than the medical triumvirate of a former era, Boerhaave, Stahl, and Hoffman, the revolution in chemistry was begun. We must add Waltire, Watt, Crawford, Kirwan, &c. in England; Wilek, Scheele, Bemen, in Sweden ; and some Germans; but the latter were more metallurgic and pharmaceutic than theoretic chemists.

A prodigious mass of new facts, and a large portion of theol'y begun, about the year 1770, to be imported from this country into France, where they attracted the attention of Lavoisier. As the claims which the French lay to the title of founders of the modern system of chemistry rest solely on the labours of

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this celebrated individual, we will examine them. In the year 1772, he began to work, first, on carbonic acid. The state of our knowledge concerning that substance then, was as follows. Paracelsus, Van Helmont, Hales, and Black, had disengaged it from earths and alkalis ; Cavendish, Priestley, Kier, Bewly, Bergman, Lane, M.Bride, Jacquin, had examined its properties; and Black had proved, by direct experiment, that it results from the combustion of coal and charcoal. In 1772, Lavoisier burnt these substances in close vessels; and thus, by a more rigorous synthesis, gave additional weight to the discovery of Black.

Ždly, With regard to diamond, Newton first asserted its combustibility; the Academy del Cimento burnt it in the focus of a lens; Macquer, Darcet, Ronelle, in a crucible; and Lavoisier in close vesselshence demonstrating its analogy with charcoal.

3dly, Previous to the experiments of Lavoisier, on the calcination of metals, Rey, Homberg, Hooke, Moyou, had ascertained the fact; as also that, during calcination, the metals acquired weight.

Athly, It had long been suspected that atmospheric air was not a simple body; but Scheele and Priestley proved its compound nature beyond a doubt. In 1774, Lavoisier, by operating in close vessels, showed that the weight acquired by metals during calcination, is exactly equal to that lost by the air in those vessels. But he was not then acquainted with the nature of the air combined, or of the change produced.

5thly, In August of the same year, Priestley discovered the gas, since named oxygen; and in 1775, Lavoisier communicated to the Academy, that, having reduced red oxide of mercury in a retort, he obtained from it a peculiar kind of air, which maintained combustion better than common air; and which he concluded to be an exceedingly pure portion of our atmosphere...

6thly, By reducing the red oxide of mercury with charcoal in close vessels, Lavoisier obtained a farther confirmation of Dr Black's opinion concerning carbonic acid. He also varied, with great sagacity, the researches to which these subjects had given rise.

7thly, Previously to this time, Lavoisier had not turned his attention toward the theory of caloric. Between 1755 and 1765, Dr Black had established his whole system upon this subject; and before 1770, it had been examined, confirmed, extended, by Irwine, Crawford, Wilek, Cullen, Watt; and, what cannot often be said in things of this nature, it came out of the mind of its author, as complete as it stands at this hour; for, since its first promulgation, not so much as a modification has been added. The same thing may be said of specific heat; yet, of both these theories, Lavoisier has been deemed the author, because a few facts had been added, and a new instrument had been applied, by La Place and him, to measure the capacities of bodies for heat. In the same manner, every fundamental proposition respecting respiration, animal heat, &c., had been determined by Black, Priestley, Crawford, &c., before Lavoisier had investigated the subject.

Sthly, The last claim of this celebrated chemist is to the decomposition of water. The compound nature of this quondam element had been long suspected, and many attempts had been made to ascertain its nature. Scheele supposed that the result of the combustion of hydrogen and oxygen was caloric. In 1776, Macquer and Sigand de la Fond found drops of water on a saucer which they held under the flame of burning hydrogen. In 1777, Bucquet supposed the product to be carbonic acid; and Lavoisier concluded it to be sulphuric or sulphureous acid. In 1787, Mr Waeltire burnt a mixture of the two gases, and observed the vessel on which he operated to be moist in the inside. In the same year, Mr Cavendish combined the two gases together, and obtained from them a ponderable and examinable quantity of water, such as enabled him firmly to assert, water . is composed of hydrogen and oxygen.' The like conclusion too was ascertained by Watt, about the same time. But, so far was Lavoisier from having any title to a participation in the glory of the discovery, that his preceding conclusions were threatened with subversion, and his whole system was tottering, because the production of hydrogen by iron, while dissolving in dilute sulphuric acid, could not be accounted for; and, so far was he from anticipating a fact so essential to his theory, that, to use the words of a philosopher whose candour never was surpassed (Mr Cavendish, Phil. Trans. Vol. 74, p. 134), 6 until he was prevailed upon to repeat the experiment himself, • he found some difficulty in believing that nearly the whole of • the two gases could be converted into water.' It is somewhat remarkable too, and not very creditable to the inductive powers of the French chemist, while it most triumphantly proves the flagitiousness of his claim, that, in the winter of 1781-2, and six months after the luminous conclusion separately drawn by Watt and Cavendish, Lavoisier, aided by Gingembre, burnt a quantity of hydrogen gas (Mem. de l'Academie des Sciences de Paris, 1783, p. 468), still in the expectation of obtaining an acid like that produced from sulphur. Finally-on

the 4th., 1783, he performed the experiment in a more convenient apparatus, and on a larger scale; and thus, eighteen months after all doubt had ceased, discovered that Cavendish was right, and obtained conviction. The French chemists who repeated these experiinents, were La Place, Monge, Meunier, Là Fevre, Gineau, Fourcroy, Vauquelin, Sequin, &c.'

With these facts and dates before the eyes of all Europe, it is difficult to conceive how Lavoisier should ever have been named as the founder of modern Chemistry. But such is the spirit of monopoly with which we have too just grounds to reproach the French upon many occasions. No sooner did discoveries begin to multiply in England, and grand conclusions force themselves upon the minds of our philosophers, than a fine opportunity of glory presented itself to France, provided that her academicians could by any means contrive to appropriate to themselves all that we had done. For this purpose, then, a junto of French chemists pounced upon the science; and, in order to wed it in indissoluble bonds, connubio stabili,' they gave their own names to every thing that belonged to it. Even while we acknowledge the services which a methodical nomenclature has rendered, we must say that it has proved the most powerful of all the means the French have employed to support their unjust claim. No nation has so often proved the little wiles of language, in all its departments, as the French ; and they very naturally concluded, that the universal currency of their dialect, which had so often furthered their political ends, might help them in their scientific intrigues.

An obvious method for Lavoisier to extricate himself from the suspicion of connivance or complicity, was to disavow the unjust pretensions which his partisans alleged in his favour. But this he did not do; and, upon a fair review of his writings and conduct, compared with the charges brought against him, and with dates, it is difficult to dispute that he stands fairly convicted of scientific plagiarism. In his publications there is not that fair and general avowal of the merits and discoveries of his forerunners, at all times just, but which became a special duty in a moment when his countrymen were preying upon the rights of every foreign philosopher. Nay, he seems studiously to have avoided the mention of all persons, whose title to originality he knew to be stronger than his own. His public illiberality to Dr Black was extreme; and, when contrasted with his private flattery, disgusting. Still worse was his conduct to Dr Priestley, on the discovery of oxygen, which he claims for himself in these words, (Lav. Elements of Chemistry.) This species of air was discovered

about thc same time by Mr Priestley, Mr Scheele, and my• self.' To which vague and slippery assertion we shall oppose the precise and simple statement of Priestley. In a pamphlet, « The Doctrine of Phlogiston Established,' published in 1800 by this truly eminent philosopher, then in America, and irr a great measure retired from science, and from Europe, he says, ' Having made the discovery (of oxygen gas) o some time before I was in Paris, in the year 1774, I mention• ed it at the table of Lavoisier, where most of the philosophical 6 people in the city were present, saying that it was a kind of "air in which a candle burnt much better than in common air; « but I had not yet given it any name. At this, all the com? pany, and Mr and Madame Lavoisier, as much as any, ex• pressed great surprise.' This occurred in 1774. In 1775, Lavoisier, of course, was in readiness to communicate his own discovery of oxygen to the Academy. Taking in all the circumstances of the case, and all collateral evidence, together with the too frequent practice of the French, at least since the days of Des Cartes, we must say that we implicitly believe Dr Priestley.

The great object of the French was to take away the merit of all Modern Chemistry from the English, and to bestow it on theinselves. Who the sharers in the spoil should be, was a secondary question, provided France was the theatre of glory. No person could have been more judiciously selected to wear the robes of triumph than Lavoisier. He had a princely for. tune; and, almost alone in the class of opulence in which he stood, he was busied upon science. He was respected in the financial world of Paris; he enjoyed the confidence of Government; in private life, he was beloved; and his mind was fraught with method and discernment. His house then became the temple of the new science. In it was erected the altar on which, while solemn dirges sung a requiem to defunct Phlogiston, the Fundamenta of Stahl were offered up as a holocaust to the vanity of French philosophers. Neither has the spirit of moncpoly diminished in proportion as the science has gained strength ; and in the Report made by Cuvier to Bonaparte, in 1808, the same injustice prevails. It is in that respect, too, that we may behold the melancholy spectacle of a man of eminent talents boving with this phrase before usurpation and despotism- A word from your Majesty can create a work which

shall surpass that of Aristotle (Hist. of Animals), as much as ' your actions surpass in splendour those of the Macedonian § conqueror.'

Upon sụmming up the evidence on both sides of the question,

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