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Orleans in 1429: which particulars are applicable to Sir William Stuart of Castelmilk, the ancestor of Mr. Stuart.-It is not our province tantas componere lites.

Two centuries ago, the ancestors of these high-born chief tains would have decided these points by the points of their swords; a thousand vassals would have fought and have fallen in the cause; and rivers of blood would have been shed. In these happy days, proofs only are brought into the field on such, occasions; argument opposes argument; ink only is shed in the contest; and many people may think that ink might have been much better employed, by a person of Mr. Stuart's ac knowleged abilities and erudition.

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ART. VI. Memoirs of the Literary and Philosophical Society of Manchester. Vol. V. Part I. 8vo. pp. 330. 6s. Boards. Cadell jun. and Davies. 1798.

OUR readers will be able to form an opinion of the aggregate merit of this volume, when we have presented to them a view of its various contents. We shall therefore proceed to notice each essay, classing them according to their subjects, and commencing with the

PHILOSOPHICAL and CHEMICAL Papers, &c.

Remarks on Dr. Priestley's Experiments and Observations relating to the Analysis of Atmospherical Air, and his Consideration's on the Doctrine of Phlogiston, and the Decomposition of Water. By Theophilus Lewis Rupp.

We have seldom seen a more perfect specimen of accurate chemical reasoning, than this essay affords: it is indeed a most complete and triumphant reply to the arguments adduced by Dr. Priestley against the system of Lavoisier; a system which, by a singular fatality, is at present combated only by that Philosopher, to whose splendid discovery of oxygen gas it is indebted for its very existence.

Dr. Priestley heated 140.5 grains of black bones in 23.75 ounce measures of atmospheric air, which were thus reduced to 20 ounce measures. He also heated 200 grains of polished steel needles in 24 ounce measures of air, which were reduced to 19.5 ounce measures: an intense heat was purposely avoided; and when the experiment was made over lime water, a thick crust was produced :-the bones rather lost weight; the iron gained a little, though very inconsiderably. Therefore, says Dr. P. since the air was diminished by heating these substances, and they did not gain any weight in the process, the phlogistication of air is not owing to the absorption of any part of it; and, during the calcination of metals and combus tion, no oxygen is absorbed.

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To this argument, Mr. Rupp replies that the circumstances of the experiments were such as to preclude the possibility of accuracy. Instead of that heterogeneous mixture which composes atmospheric air, oxygen gas should have been used: the experiments ought to have been made over mercury instead of water: 200 grains of steel are capable of uniting with twenty times a greater quantity of oxygen than was contained in the quantity of atmospheric air used: no decisive effect could therefore be expected: no account was kept of the carbonic acid gas produced. In the first experiment, the carbon of the black bones united with the oxygen of the air, forming carbonic acid,-which accounts for the diminution of the air and the slight loss of weight in the bones; and the excess of azote in the residuum arises from the decomposition of the ammonia contained in the bones. In the second experiment, carbonic acid was produced by the union of part of the oxygen of the air employed, with the carbon of the steel; and the slight increase of weight in the needles arose from the absorption of the remainder of the oxygen.

Setting aside, however, these inaccurate and therefore inconclusive experiments, we find, in Dr. Priestley's third vo'ume of his experiments on air, that ten ounce measures of dephlogisticated air (oxygen gas) being confined over mercury, and a quantity of iron turnings being introduced and fired by a lens; the air employed was reduced to 0.8 of a measure, and by washing in lime-water to 0.38. The iron being afterward weighed, "I presently found (says he) that the dephlogisti cated air had actually been imbibed by the iron."" Repeating the experiment very frequently, I always found that other quantities of iron treated in the same manner gained similar additions of weight, which was always very nearly that of the air which disappeared." The remaining iron was converted (to use Dr. P.'s own words) into a substance the same with finery cinder.

The conclusion from these experiments is obvious: but Dr. Priestley, reverting to his theory, declares in a note that it was not dephlogisticated air which was imbibed by the iron, but only the water, which he says is by far the greatest part of it :-but what, then, is become of the air? or, if six grains of water were absorbed in the first experiment, where are the 20 ounce measures of inflammable air which should have been produced? for, Dr. Priestley says that, in passing steam over red-hot iron, the iron imbibes the water, and emits its phlogiston in the shape of inflammable air.

With regard to the decomposition of azotic gas, Mr. Rupp has repeated with care, but without success, Dr. Priestley's experiments

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experiments on this subject, in which he confined rusted iron and inflammable air over water and mercury. Similar experiments with the oxyds of manganese and mercury were equally unsuccessful.

To Dr. Priestley's considerations on the doctrine of phlogis ton and the decomposition of water, Mr. Rupp thus replies:According to the Phlogistians, a metal is a compound substance consisting of a calx and phlogiston; by parting with its phlogiston, it becomes a calx; and this calx is afterward reduced by acquiring phlogiston. Dr. P. therefore contradicts his own theory, when he says, concerning the reduction by mere heat of precipitate per se, that the mercury was converted into calx by the mere absorption of vital air, without parting with any or very little of its phlogiston; and if this calx retains nearly the whole of its phlogiston, how does it happen that this substance yields the purest oxygen gas of any of the metallic oxyds? Again, this precipitate per se, if it differs from ruuping mercury only in the absorption of oxygen, should on solution in nitric acid give out nitrous gas; one of the component parts of which, according to the Phlogistians, is phlogiston but this is not the fact. Running mercury, when dissolved in nitric acid, produces copious fumes of nitrous gas; j. e. parts with much phlogiston: but yet the red oxyd which remains is as easily reducible by simple heat as precipitate per se it therefore follows that mercury, whether it has a redundancy of phlogiston or a deficiency, will in all chemical processes exhibit the same phænomena!

If steam be passed through iron heated red hot, a quantity of hydrogen gas will make its appearance; the iron will be reduced to the state of finery cinder; and the weight of the hydrogen, with the acquired weight of the iron, will be equal to that of the water employed. The Antiphlogistians explain this fact by saying that the water is decomposed ;-one of its component parts, the hydrogen, being set at liberty, and the other, oxygen, uniting with the iron, and thus forming black oxyd. Dr. P. denies the decomposition of water, and says that the hydrogen gas in this experiment is the phlogiston of the iron, and that the water is imbibed by the iron. In proof of his assertion, he mentions the impossibility of reducing the iron to its metallic state, without the addition of some substance supposed to contain phlogiston :-but, from a beautiful experiment of his own, quoted above, it appears that iron turnings, heated under mercury in oxygen gas, absorbed the oxygen, and became converted into finery cinder. In reply, Dr. P. says that oxygen gas, and all airs in general, consist almost wholly of water; and that in fact it was only the

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water in a gasseous state which was absorbed. Admitting this, the effects of steam passed through hot iron, and of iron heated in oxygen gas, ought to be the same: but, in this latter experiment, what is become of the hydrogen or phlo giston that appeared in the former? either it is retained by the iron, while in the state of finery cinder ;-or, oxygen gas contains no water.

An Analysis of the Waters of two Mineral Springs at Lemington Priors near Warwick; including Experiments tending to elucidate the Origin of the Muriatic Acid. By William Lambe, M. A. late Fellow of St. John's College, Cambridge.

It is impossible to do justice to this very ingenious and interesting paper by a brief abstract: the mere quotation of its title, we doubt not, will induce all who are fond of chemical investigations to give it a very attentive perusal. We shall, however, just mention that the memoir contains three new and very important facts; first; the existence, in these mineral waters, of a triple salt consisting of the oxymuriates of iron and manganese; secondly, the property possessed by this salt of enabling water to hold in solution a large portion of sulphate of lime; and thirdly, the similarity (or rather the identity) of the solutions of iron and manganese in water saturated with sulphurated hydrogen, with solutions of the same metals in oxymuriatic acid.

Experiments and Observations on the Preparation, and some remarkable Properties of the Oxygenated Muriate of Potash. By Mr. Thomas Hoyle, jun.

This paper contains a variety of interesting experiments, on the detonation and inflammation produced by the mixture of oxymuriate of potash with various inflammable substances. The smell of nitrous gas, produced on the decomposition of this salt by sulphuric acid, will doubtless occasion a series of accurate investigations, for the purpose of ascertaining the cause of so extraordinary a circumstance.

Experiments and Observations on Fermentation, and the Distil lation of ardent Spirit. By Joseph Collier.

The results of these experiments are of very considerable value, both to the chemical philosopher and the manufacturer. The three grand points on which they bear, are, 1. The relative value of artificial ferments. 2. Whether the fermentation ought to be carried on in open or close vessels? 3. The effects of different factitious airs on fermenting liquors.

I. Solutions of saccharine matter may be brought to a state of fermentation without the assistance of artificial ferments, but the effect is sooner brought about when they are used;

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and, of all the artificial ferments, yeast is that which produces
the greatest quantity of spirit.

II. Boerhaave and Chaptal have mentioned the free admis
sion of air as essentially necessary to fermentation, and it is an
opinion very generally entertained by the manufacturers: but
Mr. Collier has demonstrated that fermentation is not only ca-
pable of being carried on in close vessels, but that the produce
of alcohol on distillation is considerably superior when the fer-
mentation has been so conducted.

III. Different fermenting mixtures were exposed to an atmosphere of oxygen, of hydrogen, and of a mixture of the two: that which had been exposed to oxygen gas yielded the purest spirit, but even this was not equal to what would have been produced if air had been wholly excluded.

The paper concludes with some valuable practical remarks on malting, mashing, fermenting, distilling, and rectifying.

Observations on Iron and Steel. By Joseph Collier.

Mr. C. here gives an account of the reduction of iron, and of its conversion into bar-iron and steel, as practised at the Sheffield forges; and he corrects some errors on this subject, committed by Fourcroy in his Elements of Chemistry, and by Nicholson in his Chemical Dictionary, relative to the time necessary for the cementation of iron, and the mode of tempering steel.

A section and plan of a cementation-furnace accompany
the memoir.

On the Process of Bleaching with the Oxygenated Muriatic
Acid; and a Description of a new Apparatus for Bleaching Cloth's
with that Acid dissolved in Water, without the Addition of Alcali.
By Theophilus Lewis Rupp.

The importance of this memoir to the manufacturer is
hardly to be calculated. At the period of the first introduction
of the new mode of bleaching, it was found impossible, on
account of the suffocating vapours of the oxymuriatic acid, to
make use of it in open vessels; and the method of applying it
in a closed apparatus was found to be so imperfect, as to re-
duce the bleachers to the necessity of combining the acid with
potash, and employing it in open vats: by this mode, a great
expence of alcali was incurred, and the liquor, when thus neu-
tralized, lost much of its activity. The present memoir (ac-
companied with a plate) describes a very simple and effectual
apparatus for the use of the acid in close vessels, and uncom-
bined with alcali; by which is effected a saving of 40 per cent.
in the cost of the materials of the bleaching liquor.

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