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cium, and magnium, are capable of being dissolved in hydrogen gas, and on this account I think it easy to give a concise explanation of the cause of the fall of meteorilite. We know that hydrogen gas is capable of dissolving arsenic, sulphur, phosphorus, and carbon, and of forming respectively, arseniated, sulphurated, and phosphorated hydrogen; and since meteorilites generally consist of silica, alumina, and magnesia; and the metals, chromium, iron, manganese, and several others. Since then Dr. Davy has almost proved that hydrogen is capable of dissolving several metals; why, from analogy, may not hydrogen be capable, under favourable circumstances of dissolving iron, magnanese, &c. Then if a mixture of the solutions of the above metal in hydrogen be ignited by an electric spark, may not metallic particles be precipitated, and by the agency of some mechanical operation compressed into a comparatively small bulk, and appear under the form of a solid? At least this hypothesis, or rather theory, appears to me more satisfactory than the supposed projection of these stones from the lunar vol


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Mr. John Smith, of Alton-Park near Cheadle, Staffordshire, says, various opinions have been advanced by philosophers to account for the origin and appearance of those mineral substances, which have fallen from the atmosphere, called aeroliths, or more properly meteoric stones. Some have conceived them to be concretions generated in the atmosphere; others have supposed them to be projected from volcanos on the earth, and others from those of the moon. A writer in the Edinburgh Ency. (art. Astronomy, vol. ii. p. 641) has suggested the probability of their being diminutive fragments of a planet which formerly existed between the orbits of Mars and Jupiter, and which the new planets Ceres, Pallas, Juno, and Vesta composed. In the midst of this conflict of opinions, to which others might be added, who shall have the temerity to decide?— Probably it may for ages baffle all the attempts of philosophers to account satisfactorily for the substances in question.

Mr. R. T. jun. of Grantham, observes, the opinions

of philosophers respecting atmospheric stones, are all hypothetical, and by no means satisfactory. With respect to their falling from the atmosphere there is no doubt, as it has been actually ascertained, see Philosophical Transactions for 1802. In ancient history we find accounts of this nature, which until lately were regarded as fabulous, but from the certainty that such circumstances have taken place in modern times, we are now inclined to attach more credit to these accounts. In 1492 one fell in the Orkneys, and sunk a boat. A stone fell in Alsace, in 1492, which weighed two hundred and sixty-seven pounds. In 1672, two stones fell near Verona. In 1753, one fell in Bohemia, and one in France. In 1768, three fell in different parts of France. In 1790, a shower of stones fell in France, these were seen to fall. In 1795, one stone weighing fifty-six pounds was seen to fall in Yorkshire. In 1804, a stone fell in Normandy, and in April 1805, one fell in Scotland, I think near Glasgow. At the time when these stones fell, a fire-ball or luminous meteor was seen to burst with a sudden explosion like distant artillery. The weather has always been mild and serene. The stones, when picked up, have been found hot. It is very remarkable that all these stony substances which have fallen from the first records to the present time exhibit the same characters, and these bodies are unlike any others which the earth produces. Their specific gravity from 3,350 to 4,000, water being 1,000. They are composed of round bodies, having particles of metallic substances interspersed through them. The external black crust is iron slightly oxidized, and a little nickel. The internal parts are grey. The source from whence these stones proceed is not at all known. It is conceived they may be irrupted from volcanos, but this cannot be the case, as they are found in places the most remote from them.— It has been suggested that they are formed in the atmosphere, but this opinion is equally improbable.— A third conjecture is, that they fall from the moonand many other theories have been formed, all of which only tend to prove that the subject is at present inexplicable.


Mr. J. E. Savage, also sent a communication on this



Answered by Mr. I. Bn.


I am at a loss to imagine how this barbarous and farcical custom originated, unless it was invented by that favourite of the galleries, the late Mr. Suett. It is at any rate a practice more honoured in the breach than in the observance," and it must be a matter of astonishment to every person, that the managers of our theatres should suffer such an absurdity to be practised, It cannot be reprobated in stronger language than is used in the same play by Hamlet, in his instructions to the players-"O'erstep not the modesty of nature; for any thing so overdone is from the purpose of playing, whose end, both at the first, and now, was, and is, to hold as 'twere the mirror up to nature;-now this overdone, or come tardy off, though it make the unskilful laugh, cannot but make the judicious grieve; the censure of which one, must in your allowance o'erweigh a whole theatre of others.-O! reform it altogether."

Of a similar opinion is Mr. J. Baines, jun.

J. H. N. near Leeds, says, in most of Shakspeare's tragedies we find some comic characters. The Gravedigger in Hamlet is of this cast and I conceive there is no authority but that of custom, for representing him as wearing such a number of waistcoats; and that it has been originally adopted by the players, for the purpose of keeping up the attention of the spectators, and also to divert them after the more solemn scenes of the distractions of Hamlet, and the untimely death of the amiable Ophelia; but as I am quite ignorant of the etiquette of theatrical exhibitions, I am, per haps, incompetent to answer the query.

Mr. J. Bamford expressed very nearly the same opinion.


Answered by Mr. J. Baines, jun.

Dew rises in the evening; it is the moisture of the earth converted into vapour by heat; but the coldness

of the night condences it, when its falls again to the earth.


Mr. M. Harrison says, in the day time, the rays of the sun convert the surface of aqueous fluids into vapour, which the atmosphere air holds in solution. The higher regions of the atmosphere contain less vapour than the strata nearer the surface of the earth, and every stratum of air descends a little lower during the night than it was during the day, owing to the cooling and condensing of the stratum nearest the earth, which deprives vapour of its latent heat, and it be comes dew.

The same, answered by Mr. J. B

The origin and matter of dew, are doubtless from the vapour and exhalations that rise from the earth and waters; but it is still disputed, whether it is formed from the vapours ascending from the earth during the night, or from the descent of such as have been already raised through the day. The most remarkable experiment adduced in proof of its rising, is that of M. Du Fay, of the Academy of Sciences, at Paris. He supposed that if the dew ascended it must wet a body placed low down, sooner than one placed in a higher situation. To determine this, he placed two ladders against one another, meeting at their tops, spreading wide asunder at the bottom, and so tall as to reach 32 feet high. To the several steps of these, he fastened large squares of glass, placing them in such a manner that they should not overshade one another. On the trial it appeared exactly as M. Du Fay had apprehended, the lower surface of the lowest piece of glass was first wetted, then the upper surface, then the lower surface of the pane next above it, and so on, till all the pieces were wetted to the top. M. Muschenbroek, who embraced the contrary opinion, thought he had invalidated all M. Du Fay's proofs, by repeating his experiments with the same success, on a plane covered with sheet-lead. But to this M. Du Fay replied, that there was no occasion for supposing the vapour to rise through the lead, nor from the very spot; but, that as it arose from the adjoining open


ground, the continual fluctuation of the air could not but spread it abroad; and carry it thither in its ascent. -On the other hand it has been said, that the reason why dew appears first on the lower parts of bodies, may be, that in the evening, the lower part of the atmosphere is first cooled, and consequently most disposed to part with its vapours. It seems, therefore, that the subject has not yet been fully determined by the experiments which have been made, nor indeed does it appear easy to make such as shall be perfectly decisive on the matter.

Similar to the above are the communications by Mr. J. Bamford, Mr. Copsey, J. H. N. Mr. J. Smith, Mr. J. E. Savage, and Mr. R. T. jun.

Mr. A. Hirst, of Marsden, says, dew is produced by the heat of the sun in the following manner: during a summer day the ground acquires a considerable degree of heat, which causes the more fertile and wet grounds to evaporate their moisture, which is held in solution during the heat of the sun; but if it be not carried off by the wind, part of it (at least) falls down again after sunset, on being condensed by the cold. But at the same time, the earth continues to emit vapours during the night, on account of the heat communicated to it in the day time; and this will undoubtedly be condensed on the ground as it exudes; the greater portion of the dew found on rich land is thus formed by exhalation from the earth during the night, and the remainder by the condensation of vaponr already in the atmosphere, which in still weather will fall nearly equally. We never find much dew on dry roads and pavements, except after a misty night; but we frequently see very heavy dews on fertile lands, and proportionably less on barren wastes. I have lately inverted a large tub in a fertile field for several nights, and have always found dew under it the next morning, but not in such large quantities as on the adjacent grass, where the condensed vapours from the atmosphere had liberty to fall-I have also inverted the tub during the heat of the day for a few hours, and have found dew under it whilst the sun was yet up-this dew must have exuded from the ground, as described above.


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