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this very section, that air, instead of being purified, is actuala ly corrupted by the perishing body. ,

Though we are indeed most highly entertained by the instructive catalogue of experiments given in section fixth, we are yet by no means convinced of the truth they are designed to establish. The Doctor meant, in this section, to pave the way for determining the different degrees of nutrition in different bodies. With this view he collects the air emitted by them in a state of putrefaction, which he finds to be in general infiammable, mixed with a portion of fixed air. The substances which the Doctor employs in his experiments are onions, potatoes, carrots, parsnips, and other vegetables which we most commonly feed upon. But why not extend his trials to a much greater number of bodies? this was absolutely necessary to give the least plausibility to his theory; for, perhaps, such bodies as are not nutritive might yield the same kind of air, and in equal abundance. We cannot even suspect the contrary, till such experiments are first made; besides, what evidence have we to believe, that the nutritive quality in bodies is in proportion to the inflammable air they emit, or to the phlogiston they contain ? we consider this as a step which should have been first established before the least dependence can be placed on another, which is wholly supported by it. From the teftimony of universal experience it must be allowed, that animal are more nutritive than vegetable substances. And as we proceeded, we indulged the hope that the Doctor, in his next section, would have subjected animal substances to the same circumstances as those in which, agreeable to his preceding section, he had putrefied vegetable substances ; but he unexpectedly, and for what reason we cannot guess, changes the mode of his experiments : we hence derive a very entertaining list of facts, shewing the result of putrefying fielh in jars inverted in quickfilver. And though the reader may not be altogether satisfied with the Doctor's theory of nutrition, he will yet find in this section many interesting observations. Amongst others the absolute neceflity of water, and that in a confiderable quantity, to the production of some airs, viz. nitrous, fixed, and inflammable air; but while this appears to be the consequence of several experiments, the Doctor fairly acknowleges, that when water has entered into the composition of air, he knows no method of discovering and restoring it. We know of no fact which militates against this theory excepting one, which, we dare fay, the Doctor's experience will readily bring to his memory; the more concentrated the marine acid is, the greater abundance of inflammable air will it produce, if there is dissolved in it any quantity of tin or iron. We cannot account for this phenomenon, on the supposition that water enters fo abundantly into the composition of inflammable air.

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There are few speculations more curious than those which have a tendency to fhew the different degrees of phlogistication of which air is susceptible, and through which it passes -before it comes to its most putrid or noxious state. Dr. Priestley has plainly fewn that the last, or that state in which phlogiston is united to air with the strongest affinity, is the infiammable. He has pointed out some of the gradual purifications which reduce it from this state into that of phlogisticated air, or that in which a candle is extinguiñed without any attendant explofion. Section VIII. presents us with some curious instances of this process. Dr. Priestley had observed, that by introducing a mixture of iron-filings and sulphur into a jar of nitrous air, a quantity of infiammable air was generally produced : he had formerly supposed that this change was owing to some revolution in the constitution of the nitrous air; but with his usual manliness and openness, he retracts this opinion, and gives a variety of experiments, sewing that the change muft depend upon a generation of inflammable air, from the fulphur and the iron-filings. But the fame experiments, to use his own words, have led him also to the obfervation, that in this, and many other cases of the diminution of common air by phlogistic processes, a true infiammable air is first produced, and in its nascent state (as it may be called) is immediately decomposed, previous to the phlogistication of the common air.' We shall repeat some of the leading facts which confirm these observations. A mixture of iron filings and sulphur was introduced, while it was actually emitting inflammable air, into a quantity of common air ; and in the interval of a month, it diminished the common air considerably: the mixture was then taken out of the common air, and upon trial was still found to emit inflammable air. There can be no doubt that the common air in this experiment had been diminished and phlogisticated by an addition of inflammable air in its nafcent ftate, or rather after it was completely though but newly formed. Dr. Priestley wished to see whether a strong beat would not produce this change in inflammable, when already made and mixed with common air: a very simple experiment decided the contrary. A mixture of common and infiammable air, however, after being kept a long time, discovered some little change, but still there was always a residue of infiammable air: this change was produced much more completely, þy admitting the inflammable by small quantities into the common air.

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Dr. Priestley, in Section IX. examines and refutes two very important errors, which some of his philosophical friends had embraced and endeavoured to support. Dr. Ingenhousz afferts, that a quantity of air issues from the kin, and that perspiration, like respiration, phlogisticates air. Dr. Priestley proves to a demonstration, that this air does not issue from the skin, but from the water in which any part of the body subjected to trial is immersed. If you place a piece of glass or metal in water containing air, in an exhausted receiver, the phænomena, which Dr. Ingenhousz describes may be seen, in which case it is easily shewn that the air comes from the water itself; for if the water contain no air, and the surface of the glass or metal be wiped, the appearance, which Dr. Ingenhousz lays so much stress upon, cannot be produced. Dr. Ingenhousz's fupposition, that water exhausted of its air is not proper for this experiment, because it absorbs all the air as readily as it issues from the skin, is very decisively refuted by Dr. Priestley, 1. If the experiment be made in water, this must be the only unexceptionable way of doing it. 2. Water by no means abforbs

any air so fast as to give the least plausibility to Dr. Ingenhoufz's fuppofition. And, 3. This air, agreeable to Dr. Ingen housz's supposition, is phlogisticated, which we well know is of all others absorbed with the greatest difficulty. 4. “Where are the air vessels necessary for the purpose pointed out by Dr. Ingenhousz, and what is their origin and connexion with other parts of the system ; the present state of anatomy indicates nothing on the subject.' To place however the matter beyond all doubt, Dr. Priestley expelled all its air, by boiling it out of a portion of water, and plunged his arm into it; but though he continued his arm in this situation for half an hour,' not a single bubble of air made its appearance. The Doctor observes, that he might have examined whether this water contained any air besides what it might have been supposed to have imbibed from the atmosphere in this interval, but that he neglected to do it, declaring his confidence that it was unnecefsery. We are really astonished at the Doctor's carelessness in this particular instance. Why should he omit as a trifle, and leave to supposition, a fact which would have removed every hadow of an argument for the hypothesis he was endeavouring to overturn, especially as the toil it would have cost him must be so very inconsiderable ? Another error which Dr. Priestley very ably corrects in this section is a very grofs one espoused by Mr. Cruikthanks, who has declared, that perspiration actually phlogisticates air in some degree: he builds this opinion on a very flight foundation indeed, on a single experiment, in which water became turbid (after having kept

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his leg in it for some time) when he mixed it with lime-water ; one fact related by Dr. Priestley is sufficient to overturn this wild theory, which depends on the false principle, that fixed and phlogisticated are one and the fame air. Dr. Priestley tied a bladder round his leg, with his leg in this confinement he stept a whole night, and the next morning examined the air in the bladder, which he found to be equally pure with common air.

[To be continued.]

The New Annual Register, or General Repository of History, Po

litics, and Literature, for the Year 1780. To which is prea fixed, A foort Review of the principal Transaktions of the prefent Reign. 8vo. 55. 3d. in Boards. Robinson. THE HE usefulness of a Register, containing a particular ac

count of the different transactions, and the multitude of miscellaneous objects, worthy of notice, which occur in the year, is too obvious to require elucidation. In a work of so extensive a nature, next to fidelity of historical detail, the qualities moft effentially requisite are judgement in the selection of the materials, and perspicuity in the arrangement; without the former of which, the volume would become only a mass of frivolous compilation ; and without the latter, a confused and disgusting aggregate of misplaced information, and misconducted entertainment.

In the execution of the New Annual Register, we have the satisfaction to find, that due regard has been paid to those important considerations.

The historical part appears to be written with a freedom of sentiment, unbiased by political prejudices; and the various articles, relative to biographical anecdotes and characters, manners of nations, philosophical papers, antiquities, literature, &c, are not only selected from the beft authorities, but digested in a clear, methodical, and advantageous point of view,

A concise and general history of the literature of the year is also given, accompanied with observations, which will serve to ascertain the present state of learning in Britain ; and to fhew how far the genius, knowlege, and tafte of the nation, are in a declining, or a progressive condition ; a circumstance not only interesting to curiosity, but which may, eventually, be productive of consequences much more important.

This being the first volume of the work, it commences with a short review of the principal transactions of the present reign; from which, as a specimen, we have taken the following

extract.

King · King George the Second concluded his days on the twentyEfth of October, 1760, with a glory not usual to princes, and deipecially to those who have reigned for many years, and died at a very

advanced age. His abilities, if not of the first rate, were refpeétable, and his virtues rendered him the object of general esteem. There was a moderation in his political temper and conduct which fuited him to the government of a free people; and during the whole of his reign, his subjects enjoyed as great, if not a greater portion of happiness than is common to nations.

• But it was not solely, or principally, owing to these things that he went out of the world with fo much lustre. A considerable part of his reign had not a little been disturbed with political disputes : and events had happened, boch foreign and domestic, which were sutriciently mortitying, and which, at times, affected bis popularity. In the war that was concluded by the treaty of Aix-la-Chapelle, he had not been successful; and, during the courfe of that war, his throne had been thaken by a rebellion, which, however, ferved, in the end, to render it more firm, and to manifest to him the real affection of the great majority of his people. His natural attachment to Hanover, which was believed to have an undue influence upon his negotiations and engagements on the continent, had been a repeated fubject of complaint : and the comniencement of the war, in which the kingdoin was involved at his decease, had been attended with several disagree. able events. The principal circumstances that spread such a glory around him at his death, were the victories with which his latter years

had been crowned; and which were owing to a great mi. niiter, who had been forced upon him, much again it his will, by the voice of the public; but to whoin, when he had been obliged to receive him, he gave his full confidence and fupport.

The spirit and abilities of this man, which bore down all oppofition both at court and in parliament, which carried the nation along with him, and infused a noble emulation into our naval and inilitary commanders, had raised the British naine and em. pire to the highest degree of fplendor, power, and political importance.

• In this fate of the dignity and happiness of Great Britain, and in the midst of a successful war, king George the Third mounted the throne. To succeed to the crown in such a situation, was in itself a peculiar advantage; besides which there were many circuinlances ihat concurred to recommend the young monarch to the universal affection of his subjects. The time of his life, having now attained the fullage of manhood, being in his twentythird year, naturally created a prejudice in his favour; and this prejudice was justly increased by the decency and regularity of bis manners, and by the possession and the promise of many engaging virtues. There was, likewise, a disposition in all parties to unite in support of his government : for the attachment to the Stuart filmily was alınost worn out; and those who retained the frinciples which had heretofore excluded thein from the prefer.

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