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This theory, which has been univerfally received throughout Eu rope for these laft fifty years, was founded on the hypothefis that combuftible bodies contained fome fubftance which the incom buftible do not; but chemifts were never able to exhibit this fubftance in a separate ftate, and by that means to prove their hy pothefis a true one. M. Lavoifier reverfed this hypothefis, and proved by experiments, that the remains of combuftible bodies after burning, and of metals after calcination, contain a fubftance which they did not contain before. Dr. Priestley, on the other hand, inferred from a variety of experiments, that inflammable air was the phlogifton of Beccher and Stahl; and confequently that it was no longer to be regarded as a mere hypothe tical fubftance, fince he how exhibited it in a separate ftate. Mr. Cavendish's difcovery concerning the compofition of water, furnifhed new explanations for the doctrine of phlogifton. If water be compounded, fay the antiphlogiftians, of inflammable and pure air, then water will burn. A controverfy now arofe, for a general account of which we refer our Readers to the Monthly Review for April 1785, p. 241, and for May 1786, p. 321. The debate is at prefent confined to a few points; namely, whether the inflammable principle exifts, or is to be found in phlogifticated acids, vegetable acids, fixed air, fulphur, phofphorus, fugar, charcoal, and metals.

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Mr. Kirwan is aware that many ftrong prejudices favour the new opinion, which he calls the anti-phlogistic hypothefis, and its fupporters anti-phlogiftians, not by way of obloquy, but to prevent circumlocution. He feems to have laid afide all preju dices, and he endeavours, by diligent inquiries, to fhew the infufficiens of the new opinion for explaining the various chemical phenomena.

As he has, in this work, frequent occafion to calculate the weight of different kinds of air, he appropriates the first fection to a defcription of the methods which he ufed to ascertain their refpective weights. For the weight of common air, which is his ftandard, the Author is indebted to the very accurate experiments of Sir George Shuckburgh, who found the length of a column of air equiponderant to a column of mercury of an inch long. For the methods in which the Author found the weights of the other airs, we refer to the experiments, which cannot be abridged; but we fhall give his useful table of the abfolute weight of 100 cubic inches of different kinds of air at a mean height of the barometer and thermometer, and their proportions to common air. This table would have been more complete had Mr. Kirwan added another column, fhewing their proportion to water, the standard which other natural philofophers have commonly used; we fhall fupply it:

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Mr. Kirwan next treats on the compofition of acids. mines Lavoifier's doctrine of all acids being compounded of two principles, namely the peculiar acid bafts, and the oxygeneous principle; he gives that philofopher's table of the affinities of the oxygeneous principle, and makes fome juft objections to it. The acids, which Mr. Kirwan more particularly examines, are the vitriolic, nitrous, marine, aqua regia, faccharine, and phosphoric.

The vitriolic acid confifts, according to the new theory (confidered abftractedly from the water which it always contains), of fulphur united with a large portion of oxygeneous principle; according to Mr. Kirwan, it confifts of a bafis, which, when faturated with phlogifton, conftitutes fulphur; when saturated with fixed air, it becomes fixed vitriolic acid; and when with both, volatile vitriolic acid. For this view of volatile acid, Mr. K. acknowledges himself indebted to M. Bertholet; and fays, it seems to be the only improvement made in its theory fince the days of Stahl. A number of experiments are brought to support this opinion, and refute that of the antiphlogiftians.

To give a minute detail of what Mr. Kirwan has advanced on the compofition of nitrous acid, would much exceed our bounds. He makes the conftituent principles of it to be, fixed, dephlogisticated, phlogifticated, and inflammable air, all in their concrete ftaté. After the enumeration of feveral experiments to prove the presence of phlogifton in this acid, Mr. Kirwan proceeds to examine the celebrated experiment of M. Lavoifier, which firft gave rife to the antiphlogiftic theory. It appeared in the Paris Memoirs for 1776, and was noticed in the Appendix to our 65th volume, p. 491. The Academician added 1104 grains of mercury to 945 of nitrous acid: the produce was 273.234 cubic inches of nitrous air, and, by diftilling the falt to drynefs with a ftrong heat, the whole of the mercury was revived, and 287.742 inches of dephlogifticated air appeared. Hence M. Lavoifier concluded, Ift, That the nitrous acid was wholly decompofed into two fpecies of air. 2dly, That, the mercury being revived-without REV. Sept. 1787.

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lofs, there is reafon to fuppofe that it was reduced to a calx by its union with pure air, because it recovered its metallic form by the expulfion of the fame pure air. To juftify the firft conclufion, Mr. Kirwan thinks three circumftances fhould have been proved; ift, That, during the diftillation, no part of the nitrous acid had escaped into the water, over which the airs were collected. 2dly, Which is the contested point, that the nitrous air produced during folution, did not contain fome part of the mercury. 3dly, That by the re-union of the two airs, the fame quantity of acid might be reproduced. To juftify the fecond M. Lavoifier fhould have fhewn that the mercury, during its revivification, took nothing from the fubftance to which it was united while a calx, of which fubftance the pure air might have been a component part. Mr. Kirwan then gives fuch an explanation of the experiment as feems to confirm, in a fatisfactory manner, the phlogistic theory.

The marine acid comes next under confideration. The Author thinks it confifts of a peculiar bafis united to phlogiston and a certain proportion of fixed air, to both of which the bafis feems to have a strong affinity.

Aqua regia is compounded of common marine acid and strong colourless nitrous acid, the former deacidifying the latter, while the latter dephlogifticates the former; or in other words, the marine acid takes a great part of the fixed air from the nitrous acid, while the nitrous takes the phlogifton of the marine.

The phofphoric acid confifts of phofphorus united to the oxygeneous principle; but the antiphlogiftians will not allow phofphorus to contain phlogifton. If metals, in their metallic form, contain phlogifton, then phosphorus also contains phlogiston, for phofphorus precipitates metals, from their diluted folutions, in their metallic form.

The faccharine acid, Mr. Kirwan thinks, does not pre-exist in fugar, but is formed by the operation that exhibits it; it derives the greater part of its acidifying principle from the nitrous acid, which, as well as the fugar itself, is decompofed during the operation; the nitrous bafis taking up the phlogifton of the fugar, while the fixed air of the nitrous acid combines with the faccharine bafis.

The next fubject which engages Mr. Kirwan's attention is the calcination and reduction of metals. He here proves, moft fatisfactorily, the prefence of phlogiston, or inflammable air, in a concrete form, in metallic bodies endowed with metallic fplendour and peculiar coherence; and replies to the objections that have been made to his theory of fixed air, by whofe decompofition the calces of mercury are revived. He fubjoins fome curious remarks on the diffolution and precipitations of metals, and

fhews

fhews that the antiphlogiftic hypothefis is involved in many dif

ficulties.

Such is the outline of the prefent performance, which we have found to contain many curious facts, and experiments confirming them: the Author's reafoning is clofe, and though his ftyle is fometimes intricate, his conclufions feem, nevertheless, juft, and well drawn.

Before we conclude this article, we muft point out a very material typographical error, which we difcovered in p. 56. 1. 16.

where 59.8 cubic inches' occurs for, 59.8 grains troy weight. Am.

ART. XIII. Meffiah. Fifty Expofitory Difcourfes, on the Series of Scriptural Paffages, which form the Subject of the celebrated Oratorio of Handel. Preached in 1784 and 1785, at St. Mary Woolnoth, Lombard- ftreet, by John Newton, Rector. 2 Vols. 8vo. IOS. 6d. Boards. Buckland, &c. 1786.

HESE volumes feem to be published as the Author's Con

Tfeffion of faith; to declare his opinion on fome controverted points of divinity; particularly the five points that were the fubject of the famous controverfy in the laft age *. These are much enlarged upon in the course of the fermons; and the decifions are fuch as might be expected from one who has profeffed himself a Calvinist +.

The Author urges every where the Calvinift's favourite scheme of a fubftitutive fatisfaction made in the perfon of Chrift. The reader is continually called upon to judge of the propriety of fuch a fatisfaction, for the vindication of the juftice of God in the pardon of fin. Vol. i. pages 13, 89, 96. Nay, human reason (though at other times much depreciated) is now appealed to, as competent to decide, and as deciding, that thus it muft be, if finners are faved, without prejudice to the honour of the divine government.' Vol. i. p. 99. We fhall only fay, that such a fort of justice as this, which fubftitutes the innocent in the place of the guilty, as the proper object of punishment, is contrary to all human notions of juftice: contrary to every rule and maxim of juftice to be found in any book, from Ariftotle to Grotius: contrary to the practice of every court of criminal juftice in the world. What would ****** have given, might he have been allowed to ftand in the pillory by a substitute?

Befide the points which are calviniftical, there is another point every where infifted upon, peculiar to the Methodists ‡,-a di* Extent of Redemption, Election, Juftification, Effectual Grace, Free Will. + Preface to Olney Hymns.

The Quakers hold this divine teaching of the understanding; and with perfect confiftence throw the Bible away, as a dead letter, as ufelefs; a divine teaching muft fuperfede human means and authority.

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vine teaching. A teaching, not through the ordinary means common to all men, ftudy, and the inftruction of others; but a teaching by the immediate communication of the Holy Spirit. In vol. i. p. 157, the Holy Spirit is spoken of as revealing and making a clear and fatisfactory difcovery how every hindrance to the free exercife of mercy on God's part is removed, and how the demands of juftice are answered; and we are made by this revelation to understand the causes, nature, and defign of the fufferings of Chrift. They who know all this, may fairly be faid to have known the mind of the Lord; and may claim to have been his counsellors in the work of redemption.

They who think themselves thus taught of God, will not doubt but that they are taught completely, and without error; will of courfe think that those who do not agree with them, are taught by another master and this is hinted, perhaps not directly faid, in many places. Preface, p. xvi. when the Author fays,

he is not afraid of contradiction from thofe who are taught of God.' This indeed is qualified in another place. They who are taught of God, it feems, do agree in fundamentals, though perhaps not in other points. But what then are fundamentals? Why, fuch points as fpiritual perfons, who really depend on a divine teaching, are agreed in.' Vol. ii. p. 19. Well! it comes to just the fame :-you are not agreed with us, fays the Methodift; and this doctrine is fundamental:-why then, you are not a spiritual perfon, nor depend on the divine teaching; for all fuch do agree with us in fundamentals.

Mr. N. objects much to the mufic in the Abbey, vol. i. p. 64, and fays, They fet God's meffage to mufic.' Had this meffage been delivered in a few and folemn words, it might have been improper to have fet fuch words to mufic, as it undoubtedly is, to fet fome awful paffages of Scripture. But this is not the cafe. It is the poetical paffages of the Prophets, and Pfalms, and the bymns in the Revelations that are fet to mufic. We know the Píalms of David, however different their fubjects, were fet to mufic, by himself or his chief musician, and we rather fuppofe the meffage delivered by the angel" On earth peace, good will towards men," was fung by the heavenly choir. However this be, the objections here brought are general; and hold againft all anthems and choir-finging whatever. The antipathy of the modern Puritans both to the arts and fciences, exactly refembles that of their ancestors. Organs and cathedral finging were their abomination and our Author reprobates the Abbey mufic, and thinks the study of mathematics and philofophy at Cambridge ferves only to fharpen our natural proneness to vain reasoning. See Cardiphonia, vol. ii. p. 233.

We are forry to obferve, what we think an illiberal reflection the promoters of the feveral acts of toleration, from Locke

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