The term oxy

This is an able and a very elaborate article. genised is new, and adopted on the principles of the French nomenclature, which terminate in at, salts formed by the acids in ic. The inquiry was suggested by the opinion of M. Berthollet, that the oxygenised neutral contained a greater proportion of oxygen, with respect to its acid, than the acid did previous to its combination; and our author's object is to ascertain the true nature of the salt formed of muriatic acid, oxygen, and pot-ash. He endeavours to show that oxygenised and hyperoxygenised muriatic acids exist; and that, in this state, they are capable of forming saline combinations. The generic characters of the alkaline and earthy hyperoxygenised muriats we shall tran

scribe.

• Hyperoxygenized muriates are formed by passing a current of oxygenized muriatic acid through the basis, dissolved or suspended in water, as in the formation of the last mentioned genus. Their first formation is owing to the separation of the elements of an oxygenized muriate, into hyperoxygenized muriate and simple muriate; from which latter, they may be separated by crystallization, or by another process, which I shall mention, in treating of the earthy hyperoxygenized muriates. By simple trituration, they scintillate, with noise. They are decomposed by a low red heat; and give out a considerable quantity of oxygen, as they become simple muriates. They cannot be brought down, by any means that I have tried, to that diminished state of oxygenizement, which would constitute oxygenized muriates. They inflame all combustible bodies with violence, as is well known. They are soluble in water; many of them, in alcohol; and some are deliquescent. The acid is expelled, with particular phenomena, by sulphuric, nitric, and muriatic acids, without heat; and, a little below a boiling heat, by phosphoric, oxalic, tartareous, citric, and arsenic acids: but they are not acted upon by_benzoic, acetic, acetous, boracic, prussic, or carbonic acids. Those vegetable acids. which are powerful enough to decompose them, give out, towards the end, a gas of a peculiar nature, which has not so much smell as oxygenized muriatic acid gas, but which affects the eyes in an extraordinary manner, and promotes an uncommon and rather painful secretion of tears. I have not yet examined this gas, as there was invariably an inflammation of the mixture, with explosion and rupture of the vessels, almost as soon as it began to be evolved. When pure, the hyperoxygenized muriates do not precipitate any of the metallic salts, although I believe they decompose some. The order in which the bases seem to be attracted by the acid, is, potash, soda, barytes, strontia, lime, ammonia, magnesia, alumina, silica. The other earths I have not tried, and but few of the metallic oxides.' P. 138.

The different species are next described and analysed; but Mr. Chenevix thinks that a hyperoxygenised muriat of silica does not exist, and that, in no instance, is this earth dissolved by the acid in question.

The observations on metallic combinations of muriatic acid,

in its different states, are peculiarly valuable. That the muriatic acid, in corrosive sublimate, was in an oxygenised state, was first suspected, we believe, by Scopoli, who was followed by Berthollet in the year 1780. The latter author, however, altered his opinion; and he was supported by Proust; though Fourcroy, in his last work, adheres to the belief of Scopoli. Our author appears to have proved that the oxygen is only united with the salt, and that the acid is in its usual state. The proportion of oxygen is a little greater in the corrosive sublimate than in calomel; and that of the acid is also greater: for it seems that, when the metal is oxygenised, it requires a larger proportion of acid for its solution. A bit of copper, put into a solution of corrosive sublimate, precipitates calomel, which contains neither corrosive sublimate nor copper. The following remarks, on Schecle's preparation of calomel by the humid way, deserve particular attention.

By the humid way, I do not mean precisely the method of Scheele. That chemist desires us to boil the acid with the mercury, after they have ceased to act upon each other at a low temperature. By this method, the nitric acid takes up an excess of mercurial oxide; and the nitrate of mercury thus formed, precipitates by water. Therefore, when this nitrate of mercury is poured into the dilute solution of muriate of soda, according to the formula of Scheele, the action, on the part of the solution, is twofold.

Ist. The water acts upon one part, and precipitates an oxide, or rather an insoluble subnitrate of mercury. And,

2dly. A double decomposition takes place between the nitrate of mercury and the muriate of soda. It is with reason, that the medical world have supposed the calomel of Scheele to be different from that prepared in the humid way; for it is, in fact, calomel, plus an insoluble subnitrate of mercury. In the first part of Scheele's process, there is disengagement of nitrous gas, together with oxidizement and solution of some of the mercury. When he boils the acid upon the remaining mercury, there is no further disengagement of gas; yet more mercury is dissolved. The nitrate of mercury, therefore, rather contains an oxide less oxidized after ebullition than before it. The true difference is in the subnitrate of mercury, precipitated, as I before said, by the water in which the muriate of soda was dissolved. And the orange-coloured powder, which remains after an attempt to sublime Scheele's calomel, is to be attributed to the same cause. To prepare calomel in the humid way, uniform as to itself, and in all respects similar to that prepared in the dry way, it is necessary, either to use the nitric solution before it has boiled, or to pour some muriatic acid into the solution of muriate of soda, previously to mixing it with the boiled solution of nitrate of mercury. In the first case, no precaution is necessary; and, in the latter, the oxide of mercury, which the nitrate of mercury has, by boiling, taken up in excess, finds an acid which is ready to saturate it. All the mercurial oxide being thus converted into calomel, none of that subnitrate of mercury can be present.' P. 159.

A true hyperoxygenised muriat of mercury may be prepared; and our author has pointed out the process. The salt, it is said, is more soluble than corrosive sublimate. We remember it was formerly recommended to add crude sal-ammoniac to solutions of this metallic salt, to prevent its deposition; and the change produced by this addition it would be curious to ascertain.

Hyperoxygenized muriate of silver is soluble in about two parts of warm water; but, by cooling, it crystallizes in the shape of small rhomboids, opaque and dull, like nitrate of lead or of barytes. It is somewhat soluble in alcohol. Muriatic acid decomposes it; as does nitric, and even acetous acid: but the result of this decomposition is not, as might be expected, nitrate or acetite of silver. At the moment that the acid is expelled from hyperoxygenized muriate of silver, a reaction takes place among its elements: oxygen is disengaged;

and the muriatic acid remains in combination with the oxide of silver. If this fact be compared with the manner in which nitric and acetous acids act upon hyperoxygenized muriate of potash, it will give a strong proof of the proportionate affinities of all these acids for oxide of silver, in comparison with that which they exercise towards the alkali.' P. 162.

The muriatic salts, commonly called Butler's, contain the acid in its simple state; and Mr. Chenevix seems to doubt whether the common acid contains oxygen. Sulphurated hydrogen, which possesses many acid properties, does not comprise oxygen. It is not clear that the Prussic acid does so, nor can we discover that the fluoric and boracic acids are oxygenised. He doubts, therefore, whether the common acid may not, like sulphur, be a radical, and, according to its degree of oxygenation, become the muriatous and muriatic acid. This, however, cannot be correct, so far as the present state of science allows us to judge; and we must add that Mr. Chenevix's paper is greatly deficient in that lucid order which would have enabled us to give a more satisfactory analysis.

• VII. Experiments and Observations on certain stony and metalline Substances, which at different Times are said to have fallen on the Earth; also on various Kinds of native Iron. By Edward Howard, Esq. F. R.S.'

The subject of falling stones is very curious, and the explanation difficult. Where the eruption of a neighbouring volcano has preceded, their source may be easily ascertained, but that a coalescence of heterogeneous matters can take place in the air, is highly improbable. What falls from our atmosphere must have been previously raised from the earth, either projected by a volcano, or carried into the air by a whirlwind. In the first step of the inquiry, we were inclined to doubt the fact of their falling, and attributed this idea to terror or superstition; and, indeed, at this moment, the facts are but in few instances ascertained, except after volcanic explosions. The Yorkshire stone

was undoubtedly one of those from Sienna; and the story, perhaps the attestations, were imported with the stone. We think, however, that stones have sometimes fallen; but the same ac counts invariably testify that they fell either during the prevalence of a thunder-storm, or the passage-probably the dissolu tion-of a meteor. Both these phænomena occur in the regions of clouds not far above the earth; so that, at least, these stones have not had a long passage, nor can they have fallen even from the moon. The singularity, however, most striking, is, that they have very little analogy with the common minerals, but greatly resemble each other. They have no volcanic marks, and consist of a quartzose substance, martial pyrites, and iron in its metallic state, blended usually with a little nickel, forming a peculiar species of amygdaloid. All the stones that have fallen from the clouds, wherever the event has occurred, are of this nature, differing only in the proportion of these ingredients; to which must be added that they contain a considerable quantity of magnesia, discovered by chemical analysis. The iron is in a malleable state. Native iron comprising the same proportion of nickel, is found in large masses consisting of globules from which the other bodies have been washed away, and is supposed to have been equally a meteorological production. Our author's recapitulation we shall select.

It will appear, from a collected view of the preceding pages and authorities, that a number of stones asserted to have fallen under similar circumstances, have precisely the same characters. The stones from Benares, the stone from Yorkshire, that from Sienna, and a fragment of one from Bohemia, have a relation to each other not to be questioned.

1st. They have all pyrites of a peculiar character.

2dly. They have all a coating of black oxide of iron.

3dly. They all contain an alloy of iron and nickel. And,

4thly. The earths which serve to them as a sort of connecting medium, correspond in their nature, and nearly in their propor

tions.

Moreover, in the stones from Benares, pyrites and globular bodies are exceedingly distinct. In the others they are more or less definite; and that from Sienna had one of its globules transparent. Meteors, or lightning, attended the descent of the stones at Benares, and at Sienna. Such coincidence of circumstances, and the unquestionable authorities I have adduced, must, I imagine, remove all doubt as to the descent of these stony substances; for, to disbelieve on the mere ground of incomprehensibility, would be to dispute most of the works of nature.

Respecting the kinds of iron called native, they all contain nickel. The mass in South America is hollow, has concavities, and appears to have been in a soft or welding state, because it has received various impressions.

• The Siberian iron has globular concavities, in part filled with a transparent substance, which, the proportional quantity of oxide of

iron excepted, has nearly the composition of the globules in the stone from Benares.

The iron from Bohemia adheres to earthy matter studded with globular bodies.

The Senegal iron had been completely mutilated before it came under my examination.

From these facts, I shall draw no conclusion, but submit the following queries.

1st. Have not all fallen stones, and what are called native irons, the same origin?

2dly. Are all, or any, the produce or the bodies of meteors? And, lastly, Might not the stone from Yorkshire have formed a meteor in regions too elevated to be discovered?

Specimens of the Benares and Yorkshire stones have been deposited, by the president, in the British Museum.'

P. 211.

We cannot dismiss this subject without forming our own conclusion. The stones have been really seen to fall in few instances only, and these, perhaps, very generally connected with explosion. While the masses of native iron present similar appearances, it cannot be said that these stones resemble no other mineral; for these are in masses so immense, that no known power could have raised them; and, had such been found, they must, from the momentum of their fall, have sunk deep in the earth. It is then, on the whole, highly probable that these stones, when not connected with volcanic explosions, have never been precipitated from the clouds, but have been changed, in their exterior, by the electrical powers of the lightning. This has influenced the appearance of the stones, and removed the earth, which led to their discovery. It is otherwise incredible that stones of little weight should thus be deeply buried, while a mass of iron of fifteen tons-which weight must have been considerably augmented by that of its other parts, now washed away-should have sunk comparatively but to a little depth.

The last article is the meteorological journal. Six's thermometer varied from 80° to 23°, and the mean was 51.3. The range of the barometer was from 30.43 to 29.48, the mean 29.84. The rain 19.197 inches: the mean heat of April 47° 7′.

ART. II.-Illustrations of the Truth of the Christian Religion, by Edward Maltby, B. D. &c. 8vo. 5s. 6d. Boards. Riving

tons. 1802.

THE rude attacks, in late years made on our common religion, have called forth the energy of its defenders; and the con-flict has shown the ignorance, insufficiency, and obstinacy of its opponents. The more the question has been examined, the more has infidelity lost ground; and we have only to