Chaps. 15-27.

Chap. 15.—General Laws of the Planets.

There are many other secrets of nature in these points, as well as the laws to which they are subject, which might be mentioned. For example, the planet Mars, whose course is the most difficult to observe [“... quæ (stella Martis) ut maxime excentrica volvitur, motus etiam maxime dissonos habere diu visa est....;” Alexandre in Lemaire, ii. 180.], never becomes stationary when Jupiter is in the trine aspect, very rarely when he is 60 degrees from the sun, which number is one-sixth of the circuit of the heavens [“... qui numerus sexangulas mundi efficit formas.”]; nor does he ever rise in the same sign with Jupiter, except in Cancer and Leo. The star Mercury seldom has his evening risings in Pisces, but very frequently in Virgo, and his morning risings in Libra; he has also his morning rising in Aquarius, very rarely in Leo. He never becomes retrograde either in Taurus or in Gemini, nor until the 25th degree of Cancer. The Moon makes her double conjunction with the sun in no other sign except Gemini, while Sagittarius is the only sign in which she has sometimes no conjunction at all. The old and the new moon are visible on the same day or night in no other sign except Aries, and indeed it has happened very seldom to any one to have witnessed it. Prom this circumstance it was that the tale of Lynceus’s quick-sightedness originated [Lynceus was one of the Argonauts and was celebrated for the acuteness of his vision; Val. Flaccus, i. 462 et seq.]. Saturn and Mars are invisible at most for 170 days; Jupiter for 36, or, at the least, for 10 days less than this; Venus for 69, or, at the least, for 52; Mercury for 13, or, at the most, for 18 [The relative situation of these astronomical phænomena has changed since the time of Pliny, in consequence of the precession of the equinoxes. For an illustration and explanation of the various statements in this chapter I may refer to the remarks of Marcus in Ajasson, ii. 368-370.].

Chap. 16. (18.)—The Reason Why the Stars Are of Different Colours.

The difference of their colour depends on the difference in their altitudes; for they acquire a resemblance to those planets into the vapour of which they are carried, the orbit of each tinging those that approach it in each direction. A colder planet renders one that approaches it paler, one more hot renders it redder, a windy planet gives it a lowering aspect, while the sun, at the union of their apsides, or the extremity of their orbits, completely obscures them. Each of the planets has its peculiar colour [Ptolemy’s account of the colours of the planets is nearly similar to that of our author; “Candidus color Jovialis est, rutilus Martius, flavus Veneris, varius Mercurii;” De Jur. Astrol. ii. 9.]; Saturn is white, Jupiter brilliant, Mars fiery, Lucifer is glowing, Vesper refulgent, Mercury sparkling, the Moon mild; the Sun, when he rises, is blazing, afterwards he becomes radiating. The appearance of the stars, which are fixed in the firmament, is also affected by these causes. At one time we see a dense cluster of stars around the moon, when she is only half-enlightened, and when they are viewed in a serene evening; while, at another time, when the moon is full, there are so few to be seen, that we wonder whither they are fled; and this is also the case when the rays of the sun, or of any of the above-mentioned bodies [This effect cannot be produced by any of the planets, except perhaps, to a certain extent, by Venus.], have dazzled our sight. And, indeed, the moon herself is, without doubt, differently affected at different times by the rays of the sun; when she is entering them, the convexity of the heavens [“mundi.”] rendering them more feeble than when they fall upon her more directly [It is scarcely necessary to remark, that the method which Pliny employs to explain the different phases of the moon betrays his ignorance, not only of the cause of these particular phænomena, but of the general principles which affect the appearance of the heavenly bodies.]. Hence, when she is at a right angle to the sun, she is half-enlightened; when in the trine aspect, she presents an imperfect orb [“seminani ambitur orbe.” According to the interpretation of Hardouin, “Orbe non perfecto et absoluto;” “major dimidia, minor plena;” Lemaire, ii. 284.], while, in opposition, she is full. Again, when she is waning, she goes through the same gradations, and in the same order, as the three stars that are superior to the sun [As Alexandre justly remarks, our author refers here to the aspects only of the planets, not to their phases; ii. 284.].

Chap. 17. (19.)—Of the Motion of the Sun and the Cause of the Irregularity of the Days.

The Sun himself is in four different states; twice the night is equal to the day, in the Spring and in the Autumn, when he is opposed to the centre of the earth [“centrum terræ;” the equator, the part equally distant from the two poles or extremities.], in the 8th degree of Aries and Libra [It may be remarked, that the equinoxes did not actually take place at this period in the points mentioned by Pliny, but in the 28th degrees of Pisces and Virgo respectively; he appears to have conformed to the popular opinion, as we may learn from Columella, lib. ix. cap. 14. The degrees mentioned above were those fixed by the Greek astronomers who formed the celestial sphere, and which was about 138 years before the Christian æra. See the remarks of Marcus in Ajasson, ii. 246 & 373, 374.]. The length of the day and the night is then twice changed, when the day increases in length, from the winter solstice in the 8th degree of Capricorn, and afterwards, when the night increases in length from the summer solstice in the 8th degree of Cancer [The same remark applies to this as to the former observation.]. The cause of this inequality is the obliquity of the zodiac, since there is, at every moment of time, an equal portion of the firmament above and below the horizon. But the signs which mount directly upwards, when they rise, retain the light for a longer space, while those that are more oblique pass along more quickly.

Chap. 18. (20.)—Why Thunder Is Ascribed to Jupiter.

It is not generally known, what has been discovered by men who are the most eminent for their learning, in consequence of their assiduous observations of the heavens, that the fires which fall upon the earth, and receive the name of thunder-bolts, proceed from the three superior stars [“siderum.”], but principally from the one which is situated in the middle. It may perhaps depend on the superabundance of moisture from the superior orbit communicating with the heat from the inferior, which are expelled in this manner [The hypothesis of the author is, that the excess of moisture in the orbit of Saturn, and the excess of heat in that of Mars, unite in the orbit of Jupiter and are discharged in the form of thunder.]; and hence it is commonly said, the thunder-bolts are darted by Jupiter. And as, in burning wood, the burnt part is cast off with a crackling noise, so does the star throw off this celestial fire, bearing the omens of future events, even the part which is thrown off not losing its divine operation. And this takes place more particularly when the air is in an unsettled state, either because the moisture which is then collected excites the greatest quantity of fire, or because the air is disturbed, as if by the parturition of the pregnant star.

Chap. 19. (21.)—Of the Distances of the Stars.

Many persons have attempted to discover the distance of the stars from the earth, and they have published as the result, that the sun is nineteen times as far from the moon, as the moon herself is from the earth [Alexandre remarks, that Pliny mentions this, not as his own opinion, but that of many persons; for, in chap. 21, he attempts to prove mathematically, that the moon is situated at an equal distance between the sun and the earth; Lemaire, ii. 286.]. Pythagoras, who was a man of a very sagacious mind, computed the distance from the earth to the moon to be 126,000 furlongs, that from her to the sun is double this distance, and that it is three times this distance to the twelve signs [Marcus remarks upon the inconsistency between the account here given of Pythagoras’s opinion, and what is generally supposed to have been his theory of the planetary system, according to which the sun, and not the earth, is placed in the centre; Enfield’s Philosophy, i. 288, 289. Yet we find that Plato, and many others among the ancients, give us the same account of Pythagoras’s doctrine of the respective distances of the heavenly bodies; Ajasson, ii. 374. Plato in his Timæus, 9. p. 312-315, details the complicated arrangement which he supposes to constitute the proportionate distances of the planetary bodies.]; and this was also the opinion of our countryman, Gallus Sulpicius [Sulpicius has already been mentioned, in the ninth chapter of this book, as being the first among the Romans who gave a popular explanation of the cause of eclipses.].

Chap. 20. (22.)—Of the Harmony of the Stars.

Pythagoras, employing the terms that are used in music, sometimes names the distance between the Earth and the Moon a tone; from her to Mercury he supposes to be half this space, and about the same from him to Venus. From her to the Sun is a tone and a half; from the Sun to Mars is a tone, the same as from the Earth to the Moon; from him there is half a tone to Jupiter, from Jupiter to Saturn also half a tone, and thence a tone and a half to the zodiac. Hence there are seven tones, which he terms the diapason harmony [“ Διὰ πασῶν, omnibus tonis contextam harmoniam.” Hardouin in Lemaire, ii. 287.], meaning the whole compass of the notes. In this, Saturn is said to move in the Doric time, Jupiter in the Phrygian [These appellations appear to have originated from different nations having assumed different notes as the foundation or commencement of their musical scale. The Abbé Barthelemi informs us, that “the Dorians executed the same air a tone lower than the Phrygians, and the latter a tone still higher than the Lydians; hence the denomination of the Dorian, Phrygian, and Lydian modes.” It appears to have been a general practice to employ the lowest modes for the slowest airs; Anacharsis’s Travels, iii. 73, 74.], and so forth of the rest; but this is a refinement rather amusing than useful.

Chap. 21. (23.)—Of the Dimensions of the World.

The stadium is equal to 125 of our Roman paces, or 625 feet [Hence the passus will be equal to 5 Roman feet. If we estimate the Roman foot at 11·6496 English inches, we shall have the miliare of 8 stadia equal to 1618 English yards, or 142 yards less than an English statute mile. See Adam’s Roman Antiquities, p. 503; also the articles Miliare and Pes in Smith’s Dictionary of Greek and Roman Antiquities; and for the varieties of the stadium, as employed at different periods and in different countries, see the article Stadium. The stadium which Herodotus employed in measurements of Babylon has been supposed to consist of 490 English feet, while that of Xenophon and Strabo has been estimated at 505; see Ed. Rev. xlviii. 190. The Abbé Barthelemi supposes the stadium to be equal to 604 English feet; Anach. Travels, vii. 284.]. Posidonius [There appears to have been two individuals of this name, who have been confounded with each other; the one referred to by Pliny was an astronomer of Alexandria, who flourished about 260 years B.C.; the other was a native of Apamea, a stoic philosopher, who lived about two centuries later; see Aikin’s Biog. in loco; also Hardouin’s Index Auctorum, Lemaire, i. 209.] supposes that there is a space of not less than 40 stadia around the earth, whence mists [The terms in the original are respectively nubila and nubes. The lexicographers and grammarians do not appear to have accurately discriminated between these two words.], winds and clouds [The terms in the original are respectively nubila and nubes. The lexicographers and grammarians do not appear to have accurately discriminated between these two words.] proceed; beyond this he supposes that the air is pure and liquid, consisting of uninterrupted light; from the clouded region to the moon there is a space of 2,000,000 of stadia, and thence to the sun of 500,000,000 [The words in the text are “vicies centum millia” and “quinquies millia.”]. It is in consequence of this space that the sun, notwithstanding his immense magnitude, does not burn the earth. Many persons have imagined that the clouds rise to the height of 900 stadia. These points are not completely made out, and are difficult to explain; but we have given the best account of them that has been published, and if we may be allowed, in any degree, to pursue these investigations, there is one infallible geometrical principle, which we cannot reject. Not that we can ascertain the exact dimensions (for to profess to do this would be almost the act of a madman), but that the mind may have some estimate to direct its conjectures. Now it is evident that the orbit through which the sun passes consists of nearly 366 degrees, and that the diameter is always the third part and a little less than the seventh of the circumference [Archimedes estimated that the diameter of a circle is to its circumference as 1 to 3·1416; Hutton’s Dict. in loco. Ptolemy states it to be precisely as 1 to 3; Magn. Const. i. 12.]. Then taking the half of this (for the earth is placed in the centre) it will follow, that nearly one-sixth part of the immense space, which the mind conceives as constituting the orbit of the sun round the earth, will compose his altitude. That of the moon will be one-twelfth part, since her course is so much shorter than that of the sun; she is therefore carried along midway between the sun and the earth [The author’s reasoning is founded upon the supposition of the length of the sun’s path round the earth being twelve times greater than that of the moon’s; the orbit therefore would be twelve times greater and the radius in the same proportion.]. It is astonishing to what an extent the weakness of the mind will proceed, urged on by a little success, as in the above-mentioned instance, to give full scope to its impudence! Thus, having ventured to guess at the space between the sun and the earth, we do the same with respect to the heavens, because he is situated midway between them; so that we may come to know the measure of the whole world in inches. For if the diameter consist of seven parts, there will be twenty-two of the same parts in the circumference; as if we could measure the heavens by a plumb-line!

The Egyptian calculation, which was made out by Petosiris and Necepsos, supposes that each degree of the lunar orbit (which, as I have said, is the least) consists of little more than 33 stadia; in the very large orbit of Saturn the number is double; in that of the sun, which, as we have said, is in the middle [“Non inter Lunam et Saturnum, sed inter Lunam et cœlum affixarum stellarum, medium esse Solem modo dixerat. Quam parum sui meminit!” Alexandre in Lem. i. 291.], we have the half of the sum of these numbers. And this is indeed a very modest calculation [“Qui computandi modus plurimum habet verecundiæ et modestiæ, quum ibi sistit, nec ulterius progreditur.” Hardouin in Lemaire, i. 292.], since if we add to the orbit of Saturn the distance from him to the zodiac, we shall have an infinite number of degrees [“... ad Saturni circulum addito Signiferi ipsius intervallo,...”].

Chap. 22. (24.)—Of the Stars Which Appear Suddenly, or of Comets.

A few things still remain to be said concerning the world; for stars are suddenly formed in the heavens themselves; of these there are various kinds.

(25.) The Greeks name these stars comets [a κόμη, coma.]; we name them Crinitæ, as if shaggy with bloody locks, and surrounded with bristles like hair. Those stars, which have a mane hanging down from their lower part, like a long beard, are named Pogoniæ [a πωγωνίος, barbatus. Most of these terms are employed by Aristotle and by Seneca.]. Those that are named Acontiæ [ab ἀκόντιον, jaculum.] vibrate like a dart with a very quick motion. It was one of this kind which the Emperor Titus described in his very excellent poem, as having been seen in his fifth consulship; and this was the last of these bodies which has been observed. When they are short and pointed they are named Xiphiæ [a ξίφος, ensis.]; these are the pale kind; they shine like a sword and are without any rays; while we name those Discei [a δίσκος, orbis.], which, being of an amber colour, in conformity with their name, emit a few rays from their margin only. A kind named Pitheus [a πίθος, dolium. Seneca describes this species as “magnitudo vasti rotundique ignis dolio similis;” Nat. Quæst. lib. i. § 14. p. 964.] exhibits the figure of a cask, appearing convex and emitting a smoky light. The kind named Cerastias [a κέρας, cornu.] has the appearance of a horn; it is like the one which was visible when the Greeks fought at Salamis. Lampadias [a λαμπὰς, fax.] is like a burning torch; Hippias [ab ἵππος, equus. Seneca mentions the fax, the jaculum, and the lampas among the prodigies that preceded the civil wars; Phars. i. 528 et seq.] is like a horse’s mane; it has a very rapid motion, like a circle revolving on itself. There is also a white comet, with silver hair, so brilliant that it can scarcely be looked at, exhibiting, as it were, the aspect of the Deity in a human form. There are some also that are shaggy, having the appearance of a fleece, surrounded by a kind of crown. There was one, where the appearance of a mane was changed into that of a spear; it happened in the 109th olympiad, in the 398th year of the City [Alexandre remarks, that these dates do not correspond, and adds, “Desperandum est de Pliniana chronologia; nec satis interdum scio, utrum librarios, an scriptorem ipsum incusem,....” Lemaire, i. 295. According to the most approved modern chronology, the middle of the 109th olympiad corresponds to the 211th year of the City.]. The shortest time during which any one of them has been observed to be visible is 7 days, the longest 180 days.

Chap. 23.—Their Nature, Situation, and Species.

Some of them move about in the manner of planets [“errantium modo;” this may mean, that they move in orbits like those of the planets and exhibit the same phænomena, or simply that they change their situation with respect to the fixed stars.], others remain stationary. They are almost all of them seen towards the north [Seneca remarks on this point, “Placet igitur nostris (Stoicis) cometas... denso aëri creari. Ideo circa Septemtrionem frequentissime apparent, quia illic plurimi est aëris frigor.” Quæst. Nat. i. 7. Aristotle, on the contrary, remarks that comets are less frequently produced in the northern part of the heavens; Meteor. lib. i. cap. 6. p. 535.], not indeed in any particular portion of it, but generally in that white part of it which has obtained the name of the Milky Way. Aristotle informs us that several of them are to be seen at the same time [Ubi supra.], but this, as far as I know, has not been observed by any one else; also that they prognosticate high winds and great heat [See Aristotle, ut supra, p. 537.]. They are also visible in the winter months, and about the south pole, but they have no rays proceeding from them. There was a dreadful one observed by the Æthiopians and the Egyptians, to which Typhon, a king of that period, gave his own name; it had a fiery appearance, and was twisted like a spiral; its aspect was hideous, nor was it like a star, but rather like a knot of fire [“Videtur is non cometes fuisse, sed meteorus quidam ignis;” Alexandre in Lemaire, i. 296.]. Sometimes there are hairs attached to the planets and the other stars. Comets are never seen in the western part of the heavens. It is generally regarded as a terrific star, and one not easily expiated; as was the case with the civil commotions in the consulship of Octavius, and also in the war of Pompey and Cæsar [Virgil, Geor. i. 488 et seq., Manilius, i. 904 et seq., and Lucan, i. 526 et seq., all speak of the comets and meteors that were observed previous to the civil wars between Pompey and Cæsar. In reference to the existence of a comet about the time of Julius Cæsar, Playfair remarks, that Halley supposed the great comet of 1680 to have been the same that appeared in the year 44 A.C., and again in Justinian’s time, 521 P.C., and also in 1106; Elem. Nat. Phil. ii. 197, 198. See Ptolemy’s Cent. Dict. no. 100, for the opinion, that comets presented an omen especially unfavourable to kings. To this opinion the following passage in the Paradise Lost obviously refers; “And with fear of change perplexes monarchs.”]. And in our own age, about the time when Claudius Cæsar was poisoned and left the Empire to Domitius Nero, and afterwards, while the latter was Emperor [Seneca refers to the four comets that were seen, after the death of Cæsar, in the time of Augustus, of Claudius, and of Nero; Quæst. Nat. i. 7. Suetonius mentions the comet which appeared previous to the death of Claudius, cap. 46, and Tacitus that before the death of Nero, Ann. xiv. 22.], there was one which was almost constantly seen and was very frightful. It is thought important to notice towards what part it darts its beams, or from what star it receives its influence, what it resembles, and in what places it shines. If it resembles a flute, it portends something unfavourable respecting music; if it appears in the parts of the signs referred to the secret members, something respecting lewdness of manners; something respecting wit and learning, if they form a triangular or quadrangular figure with the position of some of the fixed stars; and that some one will be poisoned, if they appear in the head of either the northern or the southern serpent.

Rome is the only place in the whole world where there is a temple dedicated to a comet; it was thought by the late Emperor Augustus to be auspicious to him, from its appearing during the games which he was celebrating in honour of Venus Genetrix, not long after the death of his father Cæsar, in the College which was founded by him [“A Julio Cæsare. Is enim paulo ante obitum collegium his ludis faciendis instituerat, confecto Veneris templo;” Hardouin in Lemaire, i. 299. Jul. Obsequens refers to a “stella crinita,” which appeared during the celebration of these games, cap. 128.]. He expressed his joy in these terms: “During the very time of these games of mine, a hairy star was seen during seven days, in the part of the heavens which is under the Great Bear. It rose about the eleventh hour of the day [“Hoc est, hora fere integra ante solis occasum;” Hardouin in Lemaire, i. 299.], was very bright, and was conspicuous in all parts of the earth. The common people supposed the star to indicate, that the soul of Cæsar was admitted among the immortal Gods; under which designation it was that the star was placed on the bust which was lately consecrated in the forum [All these circumstances are detailed by Suetonius, in Julio, § 88. p. 178.].” This is what he proclaimed in public, but, in secret, he rejoiced at this auspicious omen, interpreting it as produced for himself; and, to confess the truth, it really proved a salutary omen for the world at large [“terris.”].

Some persons suppose that these stars are permanent, and that they move through their proper orbits, but that they are only visible when they recede from the sun. Others suppose that they are produced by an accidental vapour together with the force of fire, and that, from this circumstance, they are liable to be dissipated [Seneca remarks, “... quidam nullos esse cometas existimant, sed species illorum per repercussionem vicinorum siderum,... Quidam aiunt esse quidem, sed habere cursus suos et post certa lustra in conspectum mortalium exire.” He concludes by observing, “Veniet tempus, quo ista quæ nunc latent, in lucem dies extrahat, et longioris diei diligentia;” Nat. Quæst. lib. 7. § 19. p. 807.].

Chap. 24. (26.)—The Doctrine of Hipparchus About the Stars.

This same Hipparchus, who can never be sufficiently commended, as one who more especially proved the relation of the stars to man, and that our souls are a portion of heaven, discovered a new star that was produced in his own age, and, by observing its motions on the day in which it shone, he was led to doubt whether it does not often happen, that those stars have motion which we suppose to be fixed. And the same individual attempted, what might seem presumptuous even in a deity, viz. to number the stars for posterity and to express their relations by appropriate names; having previously devised instruments [Nothing is known respecting the nature of these instruments, nor have we any means of forming even a conjecture upon the subject.], by which he might mark the places and the magnitudes of each individual star. In this way it might be easily discovered, not only whether they were destroyed or produced, but whether they changed their relative positions, and likewise, whether they were increased or diminished; the heavens being thus left as an inheritance to any one, who might be found competent to complete his plan.

Chap. 25.—Examples from History of Celestial Prodigies; Faces, Lampades, and Bolides.

The faces shine brilliantly, but they are never seen excepting when they are falling [From this account it would appear, that the “fax” was what we term a falling star. “Meteora ista, super cervices nostras transeuntia, diversaque a stellis labentibus, modo aërolithis ascribenda sunt, modo vaporibus incensis aut electrica vi prognata videntur, et quamvis frequentissime recurrant, explicatione adhuc incerta indigent.” Alexandre in Lemaire, i. 302.]; one of these darted across the heavens, in the sight of all the people, at noon-day, when Germanicus Cæsar was exhibiting a show of gladiators [Seneca refers to this meteor; “Vidimus non semel flammam ingenti pilæ specie, quæ tamen in ipso cursu suo dissipata est... nec Germanici mors sine tali demonstratione fuit;” Nat. Quæst, lib. i. cap. 1. p. 683.]. There are two kinds of them; those which are called lampades and those which are called bolides, one of which latter was seen during the troubles at Mutina [This meteor is mentioned by Dion Cassius, lib. xlv. p. 278, but is described by him as a lampas.]. They differ from each other in this respect, that the faces produce a long train of light, the fore-part only being on fire; while the bolides, being entirely in a state of combustion, leave a still longer track behind them.

Chap. 26.— Trabes Celestes; Chasma Cœli.

The trabes also, which are named δοκοὶ [We may presume that the trabes are, for the most part, to be referred to the aurora borealis. The chasma and the appearances described in the twenty-seventh chapter are probably varieties of this meteor. On these phænomena we have the following remarks by Seneca: “Lucem in aëre, seu quamdam albedinem, angustam quidem, sed oblongam, de noctu quandoque visam, sereno cœlo, si parallelo situ sit, Trabem vocant; si perpendiculari, Columnam; si, cum cuspide Bolida, sive Jaculum.” Nat. Quæst. vii. 4, and again, vii. 5, “Trabes autem non transcurrunt nec prætervolant, ut faces, sed commorantur, et in eadem parte cœli collucent.”], shine in the same manner; one of these was seen at the time when the Lacedæmonians, by being conquered at sea, lost their influence in Greece. An opening sometimes takes place in the firmament, which is named chasma [Seneca describes this meteor, ubi supra, i. 14. “Sunt chasmata, cum aliquando cœli spatium discedit, et flammam dehiscens velut in abdito ostentat. Colores quoque horum omnium plurimi sunt. Quidam ruboris acerrimi, quidam evanidæ et levis flammæ, quidam candidæ lucis, quidam micantes, quidam æquabiliter et sine eruptionibus aut radiis fulvi.” Aristotle’s account of chasmata is contained in his Meteor. lib. i. cap. 5. p. 534.].

Chap. 27. (27.)—Of the Colours of the Sky and of Celestial Flame.

There is a flame of a bloody appearance (and nothing is more dreaded by mortals) which falls down upon the earth [The meteor here referred to is probably a peculiar form of the aurora borealis, which occasionally assumes a red colour. See the remarks of Fouché, in Ajasson, i. 382.], such as was seen in the third year of the 103rd olympiad, when King Philip was disturbing Greece. But my opinion is, that these, like everything else, occur at stated, natural periods, and are not produced, as some persons imagine, from a variety of causes, such as their fine genius may suggest. They have indeed been the precursors of great evils, but I conceive that the evils occurred, not because the prodigies took place, but that these took place because the evils were appointed to occur at that period [The doctrine of the author appears to be, that the prodigies are not the cause, but only the indication of the events which succeed them. This doctrine is referred to by Seneca; “Videbimus an certus omnium rerum ordo ducatur, et alia aliis ita complexa sint, ut quod antecedit, aut causa sit sequentium aut signum.” Nat. Quæst. i. 1.]. Their cause is obscure in consequence of their rarity, and therefore we are not as well acquainted with them as we are with the rising of the stars, which I have mentioned, and with eclipses and many other things.