31 is way and that th' impatient captives tend, d, preffing for relief, the mountain rend; Ver. 214. In thefe eight verfes he propofes ther caufe of lightning, and says, that not only feeds of fire, agitated and whirled about in the ds, may be kindled into flames, but the clouds nfelves contain many corpufcles of fire, which receive from the fun, or from elsewhere: this is evident from the bright and flamy sur of fome clouds: Now thefe corpufcles, or is of fire, being forced out by the wind that es and compreffes the clouds together, make ightning. Ariftotle fays, that feveral adhered is opinion, which nevertheless he confutes, i. Meteor. Empedocles held that this fire, catches in the clouds, is kindled by the beams e fun: but Anaxagoras will have it defcend the highest ether, which he holds to be T. 222. He faid in the laft place, that the of fire that are in the clouds, are driven out eftrength and violence of the wind: But in thefe four verfes, he fays, that if they are riven out in that manner, yet they muft of lity fall down, when the clouds grow thin, break, and open of themfelves: and that thence proceeds the mild and gentle lightwhofe fplendor dazzles the eyes, though no der invade the ear. this breaking, or rather rarefaction of the ds, and the falling down of the atoms that e the lightning without any thunder or noife, Doet feems to infinuate the opinion of Clidewho, as Ariftotle fays, believed lightning not real fire, but only an empty fpecies, that fay, that the cloud, being agitated, and as it ftruck and beaten in the humid part of it, htens in like manner as the fea foams and s white, if it be beaten with a rod. To this ofe too Anaximenes in Stobaus alleges the mple of the fea turning bright when the oars the waves. Thus likewife Xenophanes faid, the cloud by its motion conceives the fplendor lightens: And, laftly, Animaxander favoured opinion, when he faid, that lightning is only wind that turns bright by forcing its way ugh the blackness of the cloud Ter. 226. Hitherto the poet has treated of the fcation of lightning, which the Latins called fulgur: he is now going to difpute concerning the fulmen, by which the ancients meant the lightning, that falls and does mifchief upon earth, and which in English is called a thunderbolt: The French call it "Carreau de Foudre :" which anfwers to our denomination of it: The Greeks called it xavvis; and Aristotle defines it in these words: cò dì ásgáýav åvaxugwliv ßaè äs äxg, tãs γῆς διεχθίον, κεραυνὸς καλῶνται· i. e. the lightning, if it continues its courfe to, and dashes upon the earth, is called a thunderbolt; Lucretius, even in this difputation, confounds the words fulgur and fulmen, often ufing one for the other and indeed they both fignify lightning, and the fole dif ference is in the effects they produce: Our tranflator too does the like; nay, fometimes ufes the word thunder for lightning, particularly in this verfe, though thunder properly means only the noife. This diftinction was neceffary to be ob ferved in order to the better understanding of the following difputation; in which the poet treats of many things relating to lightning: I. Of its nature: II. How it is generated: III. Of its motion: IV. In what feafons of the year it is most frequent: And V. he inveighs against the fuperftition of fuch as afcribe thunder to Jupiter; and against the Thufcans, who drew their auguries from thunder and lightning. This difputation continues to ver. 431; and, firft, in thefe eighteen verses, he difputes of the nature of lightning, and teaches that it must confift of a fiery fubftance, because it finges and burns whatever it touches, fets fire to houfes, &c. But that it pierces through walls, that it melts gold, brafs, and other metals, that it draws out the liquor and leaves the vessel entire, must be afcribed to the fwiftnefs of its motion, and the tenuity and fubtleness of its fire. Ver. 227. For things that are blafted by lightning not only feem burnt, but retain a fulphurous fmell. Ver. 234. While the poet here takes notice of the wonderful effects of lightning, he obferves the feveral forts of it. Ariftotle allows only two; one, which he calls xavons, fmoky, which occafions the fwarthy colour of the things it blafts: the other, argòs, clear, to which he afcribes its penetration. But Pliny, lib. ii. cap. 51. adds a third fort, which he calls ficcus, dry; whofe nature, fays he, is indeed wonderful, fince by that veffels are exhaufted of their liquors, and drawn dry, while the veffels themselves remain untouched: Since gold, and filver, and brafs, are melted by it, while the bags that contain them are not fo much as finged, nor even the wax which feals them in the leaft melted, nor the impreffion difordered: Nay, what is yet more ftrange than all this, " Martia Romanorum princeps," fays he, "icta gravida, partu exanimato, ipfa citra ullum aliud incommodum vixit:" Martia, a Roman princefs, was ftruck with lightning when she was big with child; which killed the child within her; but the received no other hurt whatever. To which we may add what Seneca fays, that it melts the fword without doing any hurt to the 66 fcabbard; and all the iron of a spear, without fo PROBLEMS CONCERNING THUNDER 1. WHY is a man debilitated, and deprived of all his ftrength by lightning, even before he is actually struck by it? This was the obfervation of Thages the Thufcan, as Ammianus Marcellin. lib. xiii. witneffes. Because the blaft is quicker than the bolt: and therefore every thing is fhaken and blafted, before it is ftruck. But that which blafts is pernicious, and collected out of the Averni, fays Fliny, lib. ii. cap. 54. 2. Why, as it is reported, is not he ftruck, who either first fees the lightning, or hears the thunder? Plin. loc. cit. 6. Why is man the only animal, that lightning does not always kill outright, though it strikei any other creature dead in a moment? Plin. lib. citat The matter of lightning may be lefs noxious to man than to brutes, or, perhaps, because his Jungs are fofter and more lax, whence coming to breathe without any forcible endeavour, without ftraining, more feldom, and at longer intervals, ne does not so easily refpire and fuck in the am bient infection: Thus too it happens to the leal fish, or fea-calf. 7. Why do all things, that are ftruck with thunder, always fall down and lie on the contrary part? Plin loc. citat. The violence of the blow tumbles them down in that manner. 8. Why is a man, who is ftruck with lightning, when he is awake, found with his es winking, or half closed; and a man ftruck wha afleep, with his eyes broad open? Plin. k citat. This obfervation is not always true. But when it does happen, the reafon is, because the bodies, biafted by lightning, grow stiff in an inftant, and continue exactly in the fame fite they were in be fore; the man awake, with eyes winking and half-fhut for fear; the flceper, wakened by the fudden noife. 9. Why was it not permitted to burn the bo dy of a man thus flain? Plin. loc. citat. Becaufe, though they held that the purging fire of the funeral pile cleanfed the foul of its con tracted filth, yet they defpaired that fo great pollution would ever be admitted into their ciety. And this too was the reafon why the Greeks burnt not the bodies of fuch as laid vio Because he provides for his fafety by his flight: and, as Seneca fays. No man ever feared light-neid. iii. Quintil Declam. x. ning, without avoiding it "Nemo unquam fulmen timuit, nifi qui effugit." Nat. Quæft. lent hands on their own perfons. Servius in E lib. ii. 3. Why does one fort of lightning pierce, another dafh to pieces, and another burn? Senec. loc. citat. This depends on the quality of the thing that is ftruck, and of the matter of which the lightning is compofed which matter, if it be fubtle, and chance to light on a thin and unrefifting body, pierces it through and through: if the matter be more denfe, and meet with a more folid body, it enters it indeed, but in the penetration dashes and tears it to pieces: when the matter is bituminous, it clings to combuftible bodies, and burns them. 4. Why does it lighten more without thunder, in the night, than by day? Plin. lib. ii. cap. 54. It lightens likewife in the day time, but the coruications are drowned by the fuperior light of the fun, unless they be vaft indeed. 5. Why is it feen to lighten without thunder? Plin. lib. ii. cap. 54. It does thunder, but at too great a diftance to be heard; but if no object intercepts the flame, it may be seen at the most remote part of the horizon. 10. Why did they esteem it a piece of religion to bury them in the earth? Philoftrat. in He roic. Left beafts and birds of prey fhould margle and devour the body, or the ferryman of the Sty gian lake refufe to waft over the wandering foals. Plin. loc. cit. 11. Why are the wounds of the thunder-ftruck colder than the rest of their body? Plin. ibid. Because the heat in the other members is only fuffocated; but quite confumed in the wounded: for all fuffocated things long retain their beat; but fuch as corrupt and wafte by degrees, grow ftiff and cold immediately. 12. Why were men blafted by lightning never removed, but buried in the very place where they were ftruck wherever it happened to be? Because the law of Numa forbade funeral rites to be paid to a man killed with lightning; which would have been in fome measure done, if the body had been removed, and carried from the place where it lay. 13. Why did they bury the body of fuch a man, by heaping up dirt over it? Because they believed that to touch it would offend the gods. 14. Why were the augurs permitted to handle fuch bodies? Because holiness becomes the holy. "Sacros Jacra decent." 15. Why were the places that were blafted by lightning, hedged in and enclosed around? Left a facred thing should be trampled on una wares. 16. What means Lucan by this verse, Inclufum Thufco veneratur cefpite fulmen? Because the place was immediately efteemed acred 17. For what reafon was it thought fo? They believed that God feemed to confecrate it to himself. 18. What then was their opinion of a perfon who was killed by thunder? They feem to have had the fame opinion of im too; for Artemidorus held that a man, killd in that manner, was not polluted, but ought be worshipped as a god. 19. Why is the money melted, and the bag intouched and in like manner the fword, while he fcabbard receives no damage? Seneca in Quæft. Nat. lib. i. Q. 31. Because of the fubtle force of the lightning, hich paffes through fome things; though fuch are denfe, and refift its force, it instantly tears pieces. 20 Why are metals melted by lightning in a oment's time, while the workmen receive no mage? Sen. loc. citat. Because of the arfenical fpirits that are in the htning For even the coiners of money can nder metals fluid with a very small quantity of fenie. 21. Why does the wine ftay in a broken vessel? nec ibid. Because it is congealed by the nitral fpirits. 22. Why does not that ftiffness last above three ays? Because the remaining fulphurous fpirits, faured by the ambient air, at length overcome je nitral. Why is the wine hurtful, and even pernicious? enec. lib. cit. Q.3. By reafon of the virulence of the arfenic, that he wine has conceived; for wines will retain mething of fulphur, as we know by experience 1 Rhenith wines. Why is the venom of ferpents taken away by ightning? Because lightning confumes it: Thus the poion of scammony abates by the bare steam of ful hur; which, continued for fome time, totally akes away its cathartic virtue. Why are fome things turned black by lightding? Because, being burnt, they retain the footy marks of the fire. Why are fome things difcoloured? Because there is a lefs portion of fulphur in the lightning, and a greater of fome other combuf tible for fire alone gives iron a violet colour, and the foils that are put under precious ftones are coloured by fire only. To all which I add what Nardius relates of the wife of a certain apothecary at Florence, who had been blafted with lightning, but was ftill living in his days, and who, after that misfortune had happened to her, became, of a very cold temperament, as she had been of before, to be of a conftitution fo extremely hot, that she could fcarce endure to wear any clothes, though ever fo thin of which he gives this reafon : Because, fays he, that moft fubtle fire confumed immediately the fuperfluous humidity that had been long ftagnating in her members, and imprinted and left behind it fome of its own fiery quality. Ver. 244. In inquiring into the cause of thunder, it muth be observed, that it never thunders but when the sky is over-caft with clouds: For unless the clouds were thick and high-built, fo great a quantity of rain or hail could not fall at the fame time. Therefore, in thofe clouds you may imagine a wind agitated and whirled about in a turbulent motion, growing hot with that motion, and forcing out of the clouds many feeds or atoms of fire: And that at length the wind itfelf takes fire, either by its own motion, or by thofe fiery particles, and breaks out with a horrid roar; and that, by that violent eruption, it fo shakes and tears the parts of the clouds. that they are all shivered into hail, or diffolved into а fhower of rain. This is contained in fifty-one verfes. Ver. 252. The fame matter compofes wind, thunder, lightning, and earthquakes, that is to tay, a dry exhalation, fays Ariftotle, lib ii. Meteor cap. ult For of this dry exhalation wind is made in the air, earthquakes within the earth; fhowers, tempefts, thunder, and lightning in the clouds. Ver. 256. These four verses Lucretius has before in book iv. ver. 172. Ver. 260. Sir R Blackmore's excellent defcription of a ftorm at fea, will illuftrate this paffage of Lucretius: Horror, amazement, and defpair appear Ver. 266. Suetonius fays of Tiberius, that he was frighted at the noife of thunder, that he ran to hide himself in caves and cellars. be opened, the flames that is ripe for birth will neceffarily fall down. Ver. 299. Lucretius adds two other ways by which lightning may be caufed; the firft in nine veries. For unkindled wind breaking out of a cloud may grow hot and take fire, by the fwift nefs of its motion, and the length of its course: Nor is this in the leaft incredible, fince a ball of lead, driven with mighty force, will melt as it flies. Thus the poet and though the inftance he brings might be confirmed by feveral autho rities of the ancient poets and hiftorians, yet it ought to be reckoned among the fables of anti Ver. 268. It is therefore evident, that there can be no thunder except in thick and deep-bellied clouds, that the matter that compofes it may be included within them: For what Pliny fays to the contrary, "Catilianis prodigiis Pompeiano ex municipo M. Herennium decurionem fereno die fulmine ictum fuiffe:" and Horace, who, Carmin. lib. i. fpeaking of Jupiter, fays, that he "ple-quity: Nevertheless, no man will deny but that rumque per purnm tonantes egit equos, volucremque currum :" Thefe inftances, I fay, are no farther to be credited than that thunder may perhaps have fometimes been heard, and lightning feen by perfons, over whofe head the fky was clear: but then fome other part of the horizon must have been covered with clouds, from which the thunder and lightning broke out. Ver. 273 The poet having taught, that lightning is generated in thick and high-built clouds; he now. in thefe twenty-two verfes, farther fhows, that the fires and winds, contained within the clouds, oft produce lightning, which is followed by a roaring noife, a trembling of the earth, and a violent fhower of rain. For, firft, fays he, The clouds contain many feeds of fire: Secondly, The wind drives and compels thofe clouds, as it were, into high mountains, and by that means squeeze out of the clouds thofe particles of fire, by whose contact, or at leaft by the violence of its own motion, the wind itfelf is kindled into flame: Thirdly, When that wind is thus kindled, the lightning grown mature, cleaves the clouds, and glares around in dreadful flashes: Lafly, The thunder roars, the earth trembles, mortals are feized with confternation and difmay, and the rain falls with fuch violence, as if the heavens were defcending in the fhower. iv. many things take fire by the swiftnefs of their motion. Ver. 305. This inftance the poet brought be. fore ver. 183. See the note upon it. Ver. 308. The fecond, in these twelve verfes If the wind beat furiously upon any thing, the feeds of fire may flow together upon the stroke, ftrikes. Thus the wind takes fire, and lightning as well out of the wind as out of the thing it is made. But that fuch a confluxion of the feeds of fire may he made in that manner, is evident jection of the wind's being cold (though even that from the ftriking of fint and iron: And the obcan by no means be granted, by reafen of the fwiftnefs of their motion), is of no weight: for the nature of iron is full as cold, yet fire will fparkle out when we ftrike it. Ver. 320. Hitherto he has treated of the nature and generation of thunder, he comes now to argue of its fwiftnefs, and violence of stroke: which, fays he, may be gathered and explained from what has been faid already. For wind fit up in a cloud, rages and grows hot; ftruggles on all fides to get out of its prifon; and, therefore, where it finds a paffage, it must of neceffity burd out with mighty force and violence, in fix verfes Befides, it confits of fmooth and small particles, and therefore paffes through the void and empty Ver. 287. Milton in Paradife Regained, Book paffages of the air, in fix verfes. Add to this its And Sir R. Blackmore: Heav'n's crystal battlements, to pieces dafh'd, Torrents of water, floods of flame weight, and that too very much increased by blows, in four verses. And, laftly, in eight veries, that it falls from a great distance, and therefore every moment increafes the fwiftnefs of its mo tion: perhaps, too, it is helped forward by the air. And what wonder that a heavy body, burfting out with violence out of a clofe prifon, and fhoved forward by other bodies, falls impetuoully, and dashes to pieces all it meets in its way? Ver. 324. The balita was a warlike engine, which the ancients made ufe of in their wars to fhoot darts or ftones. It was called balifta from Báλλw, I caft. Ver. 326. In these fix verfes, he proves the fwiftnefs of lightning, from the tenuity of the atoms of which it confifts. See book ii. ver. 365. where the poet has already proved, that lightning is compofed of fmooth and fubtle principles, which is the reafon that nothing can withstand the violence of its ftroke. Ver. 332. In these four verses, the poet argues for the fwiftnefs of lightning, and the violence of heavy bodies; to which, if any external force be added, they defcend with yet greater velocity: But lightning is a heavy body, and, falling from above, is impelled by the force of the wind; therefore, it is not ftrange, that it overturns and tears to pieces whatever opposes its paffage. its blow, from the defcent that is natural to all | then this question is easy to folve; for the defcending ftone may be faid to be borne through the air, as a boat that goes down the river with the ftream; and both of them, the air as well as the ftone, move the fwifter when they are near the centre; for the air is there more thick and impure, and confequently has a greater propenfity to tend downwards: Befides, when it is arrived on the confines, as I may fay, of its journey's end, it is fwallowed up, and ingulfed as by a certain violence, and imparts the fame lot to its companion in the fall. Ver. 336. In these eight verfes, he brings his laft argument for the celerity and impetuous force of lightning, from the great distance from whence it comes; and fays of it, as Virgil of Fame, that Mobilitate viget, virefque acquirit eundo, En. iv. ver. 175. Ev'ry moment brings New vigour to her flight, new pinions to her wings. i. Ver. 340. For the feeds of thunder, like thofe of other things, wander undetermined to any certain place, but being driven by that length of violence, are determined and moved in a direct line. Ver. 350. In these twenty-two verfes, the poet folves the fourth queftion which we propofed above, in the note on ver. 226. and inquires into the reason why it thunders more frequently in the fpring and autumn than either in winter or fummer? [But this must be taken to be meant only of fome countries of Italy.] And the reafon is, fays he, becaufe, fince thunder is of a fiery nature, and breaks out of thick clouds, it is then most to be expected, when the weather is warm, and not altogether free from cold: for where there is no heat, it is in vain to look for fire, and where there is too much heat, it fuffers not the clouds to thicken. But in the fpring, and in autumn, the cold and the heat are blended together: thence proceed clouds, winds, fire, and at length tumults and tempefts in the air, and from them thunder and lightning. Ver. 344. But lightning does not break in It was anciently observed by those who made it pieces all that it falls upon for all rare bodies retheir ftudy to inquire into natural things, that main fafe and unhurt, because the fubtle fire finds the motion of all moveables is the fwifter, the a free paffage through their pores: it diffolves fobearer they approach to the place for which they lid bodies, as brafs, gold, &c. because it strikes are defigned; infomuch that they move fwifteft into their folid corpufcles, and being once entered of all when they are almost at their journey's end. into their pores, and not finding a paffage out, it Thus a ftone gives a heavier blow to a plate of disjoins the very principles, melts metals, and rebraís, or tin, for example, when it falls upon it | duces ftones into powder. from a great height, than it does when it drops from a lefs diftance: according to the variety of which distance, experience evinces, that the effect varies likewife, and that the defcending thing gains a furplufage of gravity, though not of weight. This, nevertheless, is denied by Simplicius, in his Comment upon Ariftotle de Cœlo, lib. cap. 85. where he derides this increase of gravity, and declares it a vain fiction. But we may alk him why that ftone defcends? Is it not by reafon of its weight? And fince nothing is done without caufe, why does it defcend fwifter this moment than it did the laft? Its fwiftnefs muft increase either by fome external or internal caufe: which laft can be only a more intenfe gravity: the first, Lucretius afcribes, as we have feen already in the foregoing argument, to the additional and like feeds, that the defcending ftone meets in its paffage, and that help to drive it down with greater swiftnefs. And, according to the doctrine of Epicurus, a more proper folution of this problem cannot be given. Others again afcribe it to a certain, I know not what, quality, that the medium through which it paffes imparts to it; and that fill preffes it more and more: Others impute it to the natural, fympathetical, and attractive power of the centre; to which, fay they, all heavy bodies, the nearer they approach, move the fwifter. According to which opinion, which is indeed confonant to many other experiments in nature, Cowley fings, And now the violent weight of eager love In this opinion Seneca agrees with Lucretius; and fo too does Pliny, lib. ii. cap. 50. where he teaches that it never thunders in winter and fummer, except in as much as " mitiore hyeme, et æftate nimbosâ, femper quodammodo vernat, vel autumnat;" in a mild winter, and in a cloudy fummer, the weather is neither violently cold, nor violently hot, but partakes in fome measure of the middle temperatures of the spring, or of autumn. and he strengthens this argument, by inftancing in fome countries, where by reafon of the extreme cold, as in Scythia, or of the violent heat, as in Egypt, it never thunders at all. But of thefe matters you may confult P. Gaffend. in lib. 10. Laert. de Meteorolog. Ver 370. In the fpring, and in autumn, heat and cold contend for matery: in fummer heat governs, and cold in winter. Ver. 372. Here the poet infults the college of augurs and foothfayers at Rome, who pretended to teach divination, as if it had been a fcience : this, fays he, is to know the nature of thunder, &c. |