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little and little he unfolds it. 'All thiş labow!!!
referred to the Bafha of Cairo, who is sure to divide the inst heritance among all the brothers. This sentence not being agreeable to them, they fight it out, and he that conquers, mufti have recourse to the Basha again, and pay a large tribute togberconfirmed in his dominions. It is not to be imagined, that all this is as foon done as faid; for these disputes and proceffes vlast sometimesd for two or three generations. Such of the Arab Princes as are most powerful, are most careffed by the officers of the Porte; who being liable to be removed, take cate to behave in such manner towards these princes, that in case of necessity they may have a safe retreat among them. 1,13 is
We are now arrived at the conclusion of the first volume:. the fecond is come to hand, and next month, a view of its contents will be laid before our Readers. We make no apology for the length of this article, the work is new and curiOds; is written in a foreign language, and the remarks, and explanation of Arabic words, which we have added, may be ofrufe to those who Thall read Mr. Norden's performance in 14 the original.: 039197 on toh: D,TOTEC DE 12)
lin 80*1109u ! Conclusion of the Philofophical Transactions, begun in aur laft.
sud pio sottog ni See page 271, fequl in past Arts p2s Extraits softwo Letters to Thomas Hollés, Efq; con
guid ncerning the late discoveries at Herculaneum. r*, THESE Extracts are curious, but Art. 23. is more to
hour purpose, particularly Father Antonio's method of unfolding the paper fcrolls lately discovered in the fame fub terráneous city. 3578 vos
This Friar, who is a writer at the Vatican, made a machine, with whichy" (by the means of certain threads, which • being gummed, Ituck to the back pate of the papyrus, where • there was no writing) "he begins, by degrees, to pull, while,
with a fort of engraver's inftrument, he loofens ones leaf • from the other, (which is the most difficult part of all) and • then makes a fórt of lining to the back of the papyrus, with exceeding thin leaves of onion, (if I'miftake not) and with fone fpirituous liquor, with which he wets the papyrus, by
cannot be well comprehended without seeing. With patience superior to . what a man can imagine, this good Father has unrolled a s pretty large piece of papyrus, the worst preserved, by way of trial. It is found to be the work of a Greek writer, and
is a small philosophic tract (in Plutarch's manner) on mufic; * blaming it as pernicious to fociety, and productive of foftļ ness and effeminacy. It does not discourse of the art of mu4 'fic. The beginning is wanting, but it is to be hoped, that the author's name may be found at the end : it feems how
ever to be the work of a ftoic philosopher ; becaufe Zeno is • much commended. The papyrus is written acrofs in fo • many columns, every one of about twenty lines, and every • line is the third of a palm long. Between column and co• Jumn is a void fpace of more than an inch... There are now « unrolled about thirty columns, which is about half of the
whole; this roll being one of the largest : the letters are diftinguishable enough. Father Antonio, after he has lootened
a piece, takes it off where there are no letters, and places < it between two crystals, for the better obfervation; and then • having an admirable talent in imitating characters, he copies • it with all the lacunæ, which are very numerous in this « fcorched papyrus; and gives this copy to the Canon Maz• zocchi, who tries to fupply the loss, and explain it. The • letters are capital ones, and almost without any abbreviation. • The worft is, the work takes up fo much time, that a fmall « quantity of writing requires five or fix days to unroll, fo
that a whole year is already consumed about half this roll. • The lacunæ, for the most part, are of one or two words,
that may be supplied by the context. As foon as this roll is
finifhed, they will begin a Latin one. There are some fo « voluminous, and the papyrus fo fine, that unrolled, they & would take up an hundred palms space. They tell me, that ' fome of the Latin ones are in a running hand; which con. firms the opinion of the Marquis Maffei, " That the cha“racter by us absurdly called Gothic and Lombard, is the " antient running hand corrupted by time." However, I • have not seen any of these last. The curiosity of these pa• pyri is, that there is no little staff of wood, on which they
• Thus have I told you all that I know concerning these papyri. We may
comfort ourselves, that the affair is in good hands; being under the care and conduct of fo learned an 4 antiquarian, as the Canonico Mazzocchi, and of this able 4 and adroit Father Antonio
Art. 25. Letters of Henry Eeles, Efqz. concerning the cause of the ascent of Vapour and Exhalation, and those of winds; and of the general phenomena of the weather and barometer.
There have been several hypotheses propofed, in order to account for the ascent of vapours. Des Cartes was of opinion, that the particles of water, by the action of the sun, are formed into hollow spheres, filled with the materia fubtilis; by which means they are rendered lighter than an equal bulk of air, and consequently muft afcend in it.
But as the materia fubtilis could never be proved, this theory gáve no fatisfaction to those who would not admit of any occult agent in accounting for the phænomena of nature. Instead of the materia fubtilis, they had therefore recourse to the air, and supposed, that by the action of the sun on the furface of the water, the aqueous particles are formed into bubbles, filled with a flatus, or warm air, whereby they are rendered fpecifically lighter than those of air, and therefore muft rise therein.
Those among the foreign philosophers, who maintain fire to be a particular substance, suppose, that the rays of the fun, or the particles of fire separated from them, adhere to those of the water; by which means the aqueous particles are rendered lighter than an equal bulk of air, and consequently, by the laws of hydroftatics, muft afcend in it.
Dr. Defaguliers, aware of the objections made to the above hypotheses, advanced another. He fuppofed, that the particles of water are so far feparated by heat, as to be without the fphere of each other's attraction, when they begin to repel each other, and by chat means rise from the surface of the Auid in form of a vapour, or body of particles, which are at
equal distances from each other; and becoming thus specifically lighter than the same bulk of airy particles, they will rife in the Auid body of air, till they come to that part of it which has the same gravity: where they will form what we call clouds, and will move with the current of the air in those regions.
Such are the principal hypotheses which have been advanced to account for the afcent of vapours; but all of them are liable to so many objections and difficulties, that some have, with very good reason, declared, they can think of no way of ac
counting for the rise of vapours, according to the received ? principles of philofophy *.
* See Rowning's System of Philosophy, Vol. I. p. 138. where the reader will find the several objections brought againīt these hy
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As therefore, neither impulsion, rarefaction of the air, or any alteration of the watry particles, by expansion, is sufficient to account for the ascent of vapours, our Author has advanced a new hypothesis : that of electricity,
that of electricity. He observes, that there is but one way of altering the specific gravity of the particles of vapour and exhalation, to render them lighter than air; which is, by adding to each particle a sufficient quantity of some fluid, whose elasticity and rarity are exceedingly greater than that of the air. That the electric fire is such, will be easily granted; but how far it is adapted to this purpose, can only be determined by experiments ; by the help of which Mr. Eeles has found, that all fumes arising from fire, whether
blazing or otherwise, and all steams arising from boiling or warm water, and from all other fluids, and the breath of man, and of all other animals, and all the effluvia thrown off by perspiration, are strongly electrified. And well known experiments have shewn,. First, that destultory motion by which it Aies off from an electrified body to any number of non-electrics, which are brought within the sphere of its
activity and affection, until it be equally diffused through all, spas
cuinam esibase, potheses. Wih regard to that hypothefis which some
bhavera vanced, namely, That a body divided into minute particles, will afcend in a fluid specifically lighter than itself, it is too evidently false to need a refutation for tho it be admitted, that the folidity of a globular particle increases as the cube, but the farface only as the fquare, cof the diameter, and consequently avery Imall bodies owill have much larger surfaces, in proportion to their solid contents,
than larger bodies will; yet this increase of furface, whilft the specific gravity remains the same, will as much retard its ascent as nits des scent and the proportion between the weight of a particle of one body or fluid water for instance), and the weight of a particle of the same dimensions of another Auid (as air) will be the fame as between the weights of larger masses of these fluids. Thus, leaf gold, for instance, immersed in a bason of water, will not rise to the surface; but, on the contrary, link to the bottom. Some caution, however, mutt be used in making this experiment ; for leafgold being so very tenuous, is apt to fold in immerling it in the water, and by that means confine lome particles of air, which mult render it lighter than water, and consequently it will then rise ta the surface. It is therefore necessary, after the gold is immersed, that these folds be entirely taken out, and the leaf pressed with the finger againlt the bottom, till all the particles of air are discharged, and the water brought in contact with every part of its furface; after which it will no longer ascend to the surface of the water, but, on the contrary, if raised to it, will immediately fink to the bottom by its own gravity,
Secondly, that his fire does i activity is increased by heat. riment,
. not mix with . , that it intimately pervedes water, and many other bodies, covering their superficies to a certain distance; which diftance is not in proportion to the bulk of the body electrified, but in proportion to the state of activity of the electrical fluid.
To this our Author adds, that he found by expelos any fire which fumes, or rather with the blaze or fumes of any fire; but will not mix or fly off with the fire of red hot iron, or any other metal which does not fume.
vino ? Now to thew that this electrical fire, or fluid, is the 790131 principal cause of the ascent of vapour and exhalation, we need only prove, that it attends all vapour and exhalation, and that in such quantity, as is necessary to render them specifically lighter than the lower part of the atmosphere.
I shall not undertake to determine, by what cause vapour and exhalation are detached from their masses, whether by the solar or culinary fire, or by the vibrations of the elec trical Auid, rendered more active by those fires ; tho I am 5 led to think the latter. But it is evident, that they are
emitted in exceeding minute distinct particles, and that these particles must pass through that electrical Auid which surrounds the surface of the mass ; and that, by that means
they must be equally electrified with the mass; that is, they S must be covered with the electric fluid to as great a distance Clifrom their superficies as the mass is covered, which must alSways be in proportion to the state of activity of the electrical
fuid. In which state, when they have passed the surroundSing Auid, they must be repelled by it, and also repel each e other; and if each particle of vapour, and its surrounding fluid, occupy a greater space than the fame weight of air,
they must be fitted to ascend till they come in equilibrium with the upper and rarer part of the atmosphere in where
they must float until their specific gravity is altered. As it is very difficult to aflign the magnitude of each particle of Sivapour and exhalation, and that of the surrounding fluid,
and to shew, that both taken together occupy a greater por6tion of space, than the fame weight of air, we can only apply to experimnent, to thew that it is poflible that it may
be fo; and that will few, that in all probability it 13 10 fince it is evident, that every particle must be endued with a portion of this electrical fire, or Auid, and that there is not any other sufficient cause alligned for their ascending.
6 It PLYSamo 31