Pliny, Natural History

Classical Liberal Arts Academy Logo

The text below has been adapted by William C. Michael of the Classical Liberal Arts Academy, from Riley’s translation of Pliny’s Natural History. The text may not be copied or posted online or in print, unless an active link is provided to this page. © William C. Michael, 2022.

Table of contents

Book II. An Account of the World and the Elements

Pliny, Natural History. Book II, Chapter 1. Whether the World be Finite, and Whether there be More than One World

The world, and whatever that be which we otherwise call the heavens, by the vault of which all things are enclosed, we must conceive to be a Deity, to be eternal, without bounds, neither created, nor subject, at any time, to destruction. To inquire what is beyond it is no concern of man, nor can the human mind form any conjecture respecting it. It is sacred, eternal, and without bounds, all in all; indeed including everything in itself; finite, yet like what is infinite; the most certain of all things, yet like what is uncertain, externally and internally embracing all things in itself; it is the work of nature, and itself constitutes nature.

It is madness to harass the mind, as some have done, with attempts to measure the world, and to publish these attempts; or, like others, to argue from what they have made out, that there are innumerable other worlds, and that we must believe there to be so many other natures, or that, if only one nature produced the whole, there will be so many suns and so many moons, and that each of them will have immense trains of other heavenly bodies. As if the same question would not recur at every step of our inquiry, anxious as we must be to arrive at some termination; or, as if this infinity, which we ascribe to nature, the former of all things, cannot be more easily comprehended by one single formation, especially when that is so extensive. It is madness, perfect madness, to go out of this world and to search for what is beyond it, as if one who is ignorant of his own dimensions could ascertain the measure of any thing else, or as if the human mind could see what the world itself cannot contain.

Pliny, Natural History. Book II, Chapter 2. Of the Form of the World

That it has the form of a perfect globe we learn from the name which has been uniformly given to it, as well as from numerous natural arguments. For not only does a figure of this kind return everywhere into itself and sustain itself, also including itself, requiring no adjustments, not sensible of either end or beginning in any of its parts, and is best fitted for that motion, with which, as will appear hereafter, it is continually turning round; but still more, because we perceive it, by the evidence of the sight, to be, in every part, convex and central, which could not be the case were it of any other figure.

Pliny, Natural History. Book II, Chapter 3. Of its Nature; Whence the Name is Derived

The rising and the setting of the sun clearly prove, that this globe is carried round in the space of twenty-four hours, in an eternal and never-ceasing circuit, and with incredible swiftness. I am not able to say, whether the sound caused by the whirling about of so great a mass be excessive, and, therefore, far beyond what our ears can perceive, nor, indeed, whether the resounding of so many stars, all carried along at the same time and revolving in their orbits, may not produce a kind of delightful harmony of incredible sweetness. To us, who are in the interior, the world appears to glide silently along, both by day and by night.

Various circumstances in nature prove to us, that there are impressed on the heavens innumerable figures of animals and of all kinds of objects, and that its surface is not perfectly polished like the eggs of birds, as some celebrated authors assert. For we find that the seeds of all bodies fall down from it, principally into the ocean, and, being mixed together, that a variety of monstrous forms are in this way frequently produced. And, indeed, this is evident to the eye; for, in one part, we have the figure of a wain, in another of a bear, of a bull, and of a letter; while, in the middle of them, over our heads, there is a white circle.

With respect to the name, I am influenced by the unanimous opinions of all nations. For what the Greeks, from its being ornamented, have termed κόσμος, we, from its perfect and complete elegance, have termed “mundus”. The name “cœlum”, no doubt, refers to its being engraven, as it were, with the stars, as Varro suggests. In confirmation of this idea we may adduce the Zodiac, in which are twelve figures of animals; through them it is that the sun has continued its course for so many ages.

Pliny, Natural History. Book II, Chapter 4. Of the Elements and the Planets

I do not find that any one has doubted that there are four elements. The highest of these is supposed to be fire, and hence proceed the eyes of so many glittering stars. The next is that spirit, which both the Greeks and ourselves call by the same name, air. It is by the force of this vital principle, pervading all things and mingling with all, that the earth, together with the fourth element, water, is balanced in the middle of space. These are mutually bound together, the lighter being restrained by the heavier, so that they cannot fly off; while, on the contrary, from the lighter tending upwards, the heavier are so suspended, that they cannot fall down. Thus, by an equal tendency in an opposite direction, each of them remains in its appropriate place, bound together by the never-ceasing revolution of the world, which always turning on itself, the earth falls to the lowest part and is in the middle of the whole, while it remains suspended in the centre, and, as it were, balancing this centre, in which it is suspended. So that it alone remains immoveable, whilst all things revolve round it, being connected with every other part, whilst they all rest upon it.

Between this body and the heavens there are suspended, in this aërial spirit, seven stars, separated by determinate spaces, which, on account of their motion, we call wandering, although, in reality, none are less so. The sun is carried along in the midst of these, a body of great size and power, the ruler, not only of the seasons and of the different climates, but also of the stars themselves and of the heavens. When we consider his operations, we must regard him as the life, or rather the mind of the universe, the chief regulator and the God of nature; he also lends his light to the other stars. He is most illustrious and excellent, beholding all things and hearing all things, which, I perceive, is ascribed to him exclusively by the prince of poets, Homer.

Pliny, Natural History. Book II, Chapter 5. Of God

I consider it, therefore, an indication of human weakness to inquire into the figure and form of God. For whatever God be, if there be any other God, and wherever he exists, he is all sense, all sight, all hearing, all life, all mind, and all within himself. To believe that there are a number of Gods, derived from the virtues and vices of man, as Chastity, Concord, Understanding, Hope, Honour, Clemency, and Fidelity; or, according to the opinion of Democritus, that there are only two, Punishment and Reward, indicates still greater folly. Human nature, weak and frail as it is, mindful of its own infirmity, has made these divisions, so that every one might have recourse to that which he supposed himself to stand more particularly in need of. Hence we find different names employed by different nations; the inferior deities are arranged in classes, and diseases and plagues are deified, in consequence of our anxious wish to propitiate them. It was from this cause that a temple was dedicated to Fever, at the public expense, on the Palatine Hill, and to Orbona, near the Temple of the Lares, and that an altar was elected to Good Fortune on the Esquiline. Hence we may understand how it comes to pass that there is a greater population of the Celestials than of human beings, since each individual makes a separate God for himself, adopting his own Juno and his own Genius. And there are nations who make Gods of certain animals, and even certain obscene things, which are not to be spoken of, swearing by stinking meats and such like. To suppose that marriages are contracted between the Gods, and that, during so long a period, there should have been no issue from them, that some of them should be old and always grey-headed and others young and like children, some of a dark, complexion, winged, lame, produced from eggs, living and dying on alternate days, is sufficiently puerile and foolish. But it is the height of impudence to imagine, that adultery takes place between them, that they have contests and quarrels, and that there are Gods of theft and of various crimes. To assist man is to be a God; this is the path to eternal glory. This is the path which the Roman nobles formerly pursued, and this is the path which is now pursued by the greatest ruler of our age, Vespasian Augustus, he who has come to the relief of an exhausted empire, as well as by his sons. This was the ancient mode of remunerating those who deserved it, to regard them as Gods. For the names of all the Gods, as well as of the stars that I have mentioned above, have been derived from their services to mankind. And with respect to Jupiter and Mercury, and the rest of the celestial nomenclature, who does not admit that they have reference to certain natural phenomena?

But it is ridiculous to suppose, that the great head of all things, whatever it be, pays any regard to human affairs. Can we believe, or rather can there be any doubt, that it is not polluted by such a disagreeable and complicated office? It is not easy to determine which opinion would be most for the advantage of mankind, since we observe some who have no respect for the Gods, and others who carry it to a scandalous excess. They are slaves to foreign ceremonies; they carry on their fingers the Gods and the monsters whom they worship; they condemn and they lay great stress on certain kinds of food; they impose on themselves dreadful ordinances, not even sleeping quietly. They do not marry or adopt children, or indeed do anything else, without the sanction of their sacred rites. There are others, on the contrary, who will cheat in the very Capitol, and will forswear themselves even by Jupiter Tonans, and while these thrive in their crimes, the others torment themselves with their superstitions to no purpose.

Among these discordant opinions mankind have discovered for themselves a kind of intermediate deity, by which our scepticism concerning God is still increased. For all over the world, in all places, and at all times, Fortune is the only god whom every one invokes; she alone is spoken of, she alone is accused and is supposed to be guilty; she alone is in our thoughts, is praised and blamed, and is loaded with reproaches; wavering as she is, conceived by the generality of mankind to be blind, wandering, inconstant, uncertain, variable, and often favouring the unworthy. To her are referred all our losses and all our gains, and in casting up the accounts of mortals she alone balances the two pages of our sheet. We are so much in the power of chance, that chance itself is considered as a God, and the existence of God becomes doubtful.

But there are others who reject this principle and assign events to the influence of the stars, and to the laws of our nativity; they suppose that God, once for all, issues his decrees and never afterwards interferes. This opinion begins to gain ground, and both the learned and the unlearned vulgar are falling into it. Hence we have the admonitions of thunder, the warnings of oracles, the predictions of soothsayers, and things too trifling to be mentioned, as sneezing and stumbling with the feet reckoned among omens. The late Emperor Augustus relates, that he put the left shoe on the wrong foot, the day when he was near being assaulted by his soldiers. And such things as these so embarrass improvident mortals, that among all of them this alone is certain, that there is nothing certain, and that there is nothing more proud or more wretched than man. For other animals have no care but to provide for their subsistence, for which the spontaneous kindness of nature is all-sufficient; and this one circumstance renders their lot more especially preferable, that they never think about glory, or money, or ambition, and, above all, that they never reflect on death.

The belief, however, that on these points the Gods superintend human affairs is useful to us, as well as that the punishment of crimes, although sometimes tardy, from the Deity being occupied with such a mass of business, is never entirely remitted, and that the human race was not made the next in rank to himself, in order that they might be degraded like brutes. And indeed this constitutes the great comfort in this imperfect state of man, that even the Deity cannot do everything. For he cannot procure death for himself, even if he wished it, which, so numerous are the evils of life, has been granted to man as our chief good. Nor can he make mortals immortal, or recall to life those who are dead; nor can he effect, that he who has once lived shall not have lived, or that he who has enjoyed honours shall not have enjoyed them; nor has he any influence over past events but to cause them to be forgotten. And, if we illustrate the nature of our connexion with God by a less serious argument, he cannot make twice ten not to be twenty, and many other things of this kind. By these considerations the power of Nature is clearly proved, and is shown to be what we call God. It is not foreign to the subject to have digressed into these matters, familiar as they are to every one, from the continual discussions that take place respecting God.

Pliny, Natural History. Book II, Chapter 6. Of the Nature of the Stars; of the MotIOn of the Planets

Let us return from this digression to the other parts of nature. The stars which are described as fixed in the heavens, are not, as the vulgar suppose, attached each of them to different individuals, the brighter to the rich, those that are less so to the poor, and the dim to the aged, shining according to the lot of the individual, and separately assigned to mortals; for they have neither come into existence, nor do they perish in connexion with particular persons, nor does a falling star indicate that any one is dead. We are not so closely connected with the heavens as that the shining of the stars is affected by our death. When they are supposed to shoot or fall, they throw out, by the force of their fire, as if from an excess of nutriment, the superabundance of the humour which they have absorbed, as we observe to take place from the oil in our lamps, when they are burning. The nature of the celestial bodies is eternal, being interwoven, as it were, with the world, and, by this union, rendering it solid; but they exert their most powerful influence on the earth. This, notwithstanding its subtilty, may be known by the clearness and the magnitude of the effect, as we shall point out in the proper place. The account of the circles of the heavens will be better understood when we come to speak of the earth, since they have all a reference to it; except what has been discovered respecting the Zodiac, which I shall now detail.

Anaximander the Milesian, in the 58th olympiad, is said to have been the first who understood its obliquity, and thus opened the road to a correct knowledge of the subject. Afterwards Cleostratus made the signs in it, first marking those of Aries and Sagittarius; Atlas had formed the sphere long before this time. But now, leaving the further consideration of this subject, we must treat of the bodies that are situated between the earth and the heavens.

It is certain that the star called Saturn is the highest, and therefore appears the smallest, that he passes through the largest circuit, and that he is at least thirty years in completing it. The course of all the planets, and among others of the Sun, and the Moon, is in the contrary direction to that of the heavens, that is towards the left, while the heavens are rapidly carried about to the right. And although, by the stars constantly revolving with immense velocity, they are raised up, and hurried on to the part where they set, yet they are all forced, by a motion of their own, in an opposite direction; and this is so ordered, lest the air, being always moved in the same direction, by the constant whirling of the heavens, should accumulate into one mass, whereas now it is divided and separated and beaten into small pieces, by the opposite motion of the different stars. Saturn is a star of a cold and rigid nature, while the orbit of Jupiter is much lower, and is carried round in twelve years. The next star, Mars, which some persons call Hercules, is of a fiery and burning nature, and from its nearness to the sun is carried round in little less than two years. In consequence of the excessive heat of this star and the rigidity of Saturn, Jupiter, which is interposed between the two, is tempered by both of them, and is thus rendered salutary. The path of the Sun consists of 360 degrees; but, in order that the shadow may return to the same point of the dial, we are obliged to add, in each year, five days and the fourth part of a day. On this account an intercalary day is given to every fifth year, that the period of the seasons may agree with that of the Sun.

Below the Sun revolves the great star called Venus, wandering with an alternate motion, and, even in its surnames, rivalling the Sun and the Moon. For when it precedes the day and rises in the morning, it receives the name of Lucifer, as if it were another sun, hastening on the day. On the contrary, when it shines in the west, it is named Vesper, as prolonging the light, and performing the office of the moon. Pythagoras, the Samian, was the first who discovered its nature, about the 62nd olympiad, in the 222nd year of the City. It excels all the other stars in size, and its brilliancy is so considerable, that it is the only star which produces a shadow by its rays. There has, consequently, been great interest made for its name; some have called it the star of Juno, others of Isis, and others of the Mother of the Gods. By its influence everything in the earth is generated. For, as it rises in either direction, it sprinkles everything with its genial dew, and not only matures the productions of the earth, but stimulates all living things. It completes the circuit of the zodiac in 348 days, never receding from the sun more than 46 degrees, according to Timæus.

Similarly circumstanced, but by no means equal in size and in power, next to it, is the star Mercury, by some called Apollo; it is carried in a lower orbit, and moves in a course which is quicker by nine days, shining sometimes before the rising of the sun, and at other times after its setting, but never going farther from it than 23 degrees, as we learn from Timæus and Sosigenes. The nature of these two stars is peculiar, and is not the same with those mentioned above, for those are seen to recede from the sun through one-third or one-fourth part of the heavens, and are often seen opposite to it. They have also other larger circuits, in which they make their complete revolutions, as will be described in the account of the great year.

But the Moon, which is the last of the stars, and the one the most connected with the earth, the remedy provided by nature for darkness, excels all the others in its admirable qualities. By the variety of appearances which it assumes, it puzzles the observers, mortified that they should be the most ignorant concerning that star which is the nearest to them. She is always either waxing or waning; sometimes her disc is curved into horns, sometimes it is divided into two equal portions, and at other times it is swelled out into a full orb; sometimes she appears spotted and suddenly becomes very bright; she appears very large with her full orb and suddenly becomes invisible; now continuing during all the night, now rising late, and now aiding the light of the sun during a part of the day; becoming eclipsed and yet being visible while she is eclipsed; concealing herself at the end of the month and yet not supposed to be eclipsed. Sometimes she is low down, sometimes she is high up, and that not according to one uniform course, being at one time raised up to the heavens, at other times almost contiguous to the mountains; now elevated in the north, now depressed in the south; all which circumstances having been noticed by Endymion, a report was spread about, that he was in love with the moon. We are not indeed sufficiently grateful to those, who, with so much labour and care, have enlightened us with this light; while, so diseased is the human mind, that we take pleasure in writing the annals of blood and slaughter, in order that the crimes of men may be made known to those who are ignorant of the constitution of the world itself.

Being nearest to the axis, and therefore having the smallest orbit, the Moon passes in twenty-seven days and the one-third part of a day, through the same space for which Saturn, the highest of the planets, as was stated above, requires thirty years. After remaining for two days in conjunction with the sun, on the thirtieth day she again very slowly emerges to pursue her accustomed course. I know not whether she ought not to be considered as our instructress in everything that can be known respecting the heavens; as that the year is divided into the twelve divisions of the months, since she follows the sun for the same number of times, until he returns to the commencement of his course; and that her brightness, as well as that of the other stars, is regulated by that of the sun, if indeed they all of them shine by light borrowed from him, such as we see floating about, when it is reflected from the surface of water. On this account it is that she dissolves so much moisture, by a gentle and less perfect force, and adds to the quantity of that which the rays of the sun consume. On this account she appears with an unequal light, because being full only when she is in opposition, on all the remaining days she shows only so much of herself to the earth as she receives light from the sun. She is not seen in conjunction, because, at that time, she sends back the whole stream of light to the source whence she has derived it. That the stars generally are nourished by the terrestrial moisture is evident, because, when the moon is only half visible she is sometimes seen spotted, her power of absorbing moisture not having been powerful enough; for the spots are nothing else than the dregs of the earth drawn up along with the moisture. But her eclipses and those of the sun, the most wonderful of all the phenomena of nature, and which are like prodigies, serve to indicate the magnitude of these bodies and the shadow which they cast.

Pliny, Natural History. Book II, Chapter 7. Of the Eclipses of the Moon and the Sun

For it is evident that the sun is hid by the intervention of the moon, and the moon by the opposition of the earth, and that these changes are mutual, the moon, by her interposition, taking the rays of the sun from the earth, and the earth from the moon. As she advances darkness is suddenly produced, and again the sun is obscured by her shade; for night is nothing more than the shade of the earth. The figure of this shade is like that of a pyramid or an inverted top; and the moon enters it only near its point, and it does not exceed the height of the moon, for there is no other star which is obscured in the same manner, while a figure of this kind always terminates in a point. The flight of birds, when very lofty, shows that shadows do not extend beyond a certain distance; their limit appears to be the termination of the air and the commencement of the æther. Above the moon everything is pure and full of an eternal light. The stars are visible to us in the night, in the same way that other luminous bodies are seen in the dark. It is from these causes that the moon is eclipsed during the night. The two kinds of eclipses are not, however, at the stated monthly periods, on account of the obliquity of the zodiac, and the irregularly wandering course of the moon, as stated above; besides that the motions of these stars do not always occur exactly at the same points.

Pliny, Natural History. Book II, Chapter 8. Of the Magnitude of the Stars

This kind of reasoning carries the human mind to the heavens, and by contemplating the world as it were from thence, it discloses to us the magnitude of the three greatest bodies in nature. For the sun could not be entirely concealed from the earth, by the intervention of the moon, if the earth were greater than the moon. And the vast size of the third body, the sun, is manifest from that of the other two, so that it is not necessary to scrutinize its size, by arguing from its visible appearance, or from any conjectures of the mind; it must be immense, because the shadows of rows of trees, extending for any number of miles, are disposed in right lines, as if the sun were in the middle of space. Also, because, at the equinox, he is vertical to all the inhabitants of the southern districts at the same time; also, because the shadows of all the people who live on this side of the tropic fall, at noon, towards the north, and, at sunrise, point to the west. But this could not be the case unless the sun were much greater than the earth; nor, unless it much exceeded Mount Ida in breadth, could he be seen when he rises, passing considerably beyond it to the right and to the left, especially, considering that it is separated by so great an interval.

The eclipse of the moon affords an undoubted argument of the sun’s magnitude, as it also does of the small size of the earth. For there are shadows of three figures, and it is evident, that if the body which produces the shadow be equal to the light, then it will be thrown off in the form of a pillar, and have no termination. If the body be greater than the light, the shadow will be in the form of an inverted cone the bottom being the narrowest part, and being, at the same time, of an infinite length. If the body be less than the light, then we shall have the figure of a pyramid, terminating in a point. Now of this last kind is the shadow which produces the eclipse of the moon, and this is so manifest that there can be no doubt remaining, that the earth is exceeded in magnitude by the sun, a circumstance which is indeed indicated by the silent declaration of nature herself. For why does he recede from us at the winter half of the year? That by the darkness of the nights the earth may be refreshed, which otherwise would be burned up, as indeed it is in certain parts; so great is his size.

Pliny, Natural History. Book II, Chapter 9. An Account of the Observations that have been made on the Heavens by Different Individuals

The first among the Romans, who explained to the people at large the cause of the two kinds of eclipses, was Sulpicius Gallus, who was consul along with Marcellus; and when he was only a military tribune he relieved the army from great anxiety the day before king Perseus was conquered by Paulus; for he was brought by the general into a public assembly, in order to predict the eclipse, of which he afterwards gave an account in a separate treatise. Among the Greeks, Thales the Milesian first investigated the subject, in the fourth year of the forty-eighth olympiad, predicting the eclipse of the sun which took place in the reign of Alyattes, in the 170th year of the City. After them Hipparchus calculated the course of both these stars for the term of 600 years, including the months, days, and hours, the situation of the different places and the aspects adapted to each of them; all this has been confirmed by experience, and could only be acquired by partaking, as it were, in the councils of nature. These were indeed great men, superior to ordinary mortals, who having discovered the laws of these divine bodies, relieved the miserable mind of man from the fear which he had of eclipses, as foretelling some dreadful events or the destruction of the stars. This alarm is freely acknowledged in the sublime strains of Stesichorus and Pindar, as being produced by an eclipse of the sun. And with respect to the eclipse of the moon, mortals impute it to witchcraft, and therefore endeavour to aid her by producing discordant sounds. In consequence of this kind of terror it was that Nicias, the general of the Athenians, being ignorant of the cause, was afraid to lead out the fleet, and brought great distress on his troops. Hail to your genius, ye interpreters of heaven! ye who comprehend the nature of things, and who have discovered a mode of reasoning by which ye have conquered both gods and men! For who is there, in observing these things and seeing the labours which the stars are compelled to undergo (since we have chosen to apply this term to them), that would not cheerfully submit to his fate, as one born to die? I shall now, in a brief and summary manner, touch on those points in which we are agreed, giving the reasons where it is necessary to do so; for this is not a work of profound argument, nor is it less wonderful to be able to suggest a probable cause for everything, than to give a complete account of a few of them only.

The first among the Romans, who explained to the people at large the cause of the two kinds of eclipses, was Sulpicius Gallus, who was consul along with Marcellus; and when he was only a military tribune he relieved the army from great anxiety the day before king Perseus was conquered by Paulus; for he was brought by the general into a public assembly, in order to predict the eclipse, of which he afterwards gave an account in a separate treatise. Among the Greeks, Thales the Milesian first investigated the subject, in the fourth year of the forty-eighth olympiad, predicting the eclipse of the sun which took place in the reign of Alyattes, in the 170th year of the City. After them Hipparchus calculated the course of both these stars for the term of 600 years, including the months, days, and hours, the situation of the different places and the aspects adapted to each of them; all this has been confirmed by experience, and could only be acquired by partaking, as it were, in the councils of nature. These were indeed great men, superior to ordinary mortals, who having discovered the laws of these divine bodies, relieved the miserable mind of man from the fear which he had of eclipses, as foretelling some dreadful events or the destruction of the stars. This alarm is freely acknowledged in the sublime strains of Stesichorus and Pindar, as being produced by an eclipse of the sun. And with respect to the eclipse of the moon, mortals impute it to witchcraft, and therefore endeavour to aid her by producing discordant sounds. In consequence of this kind of terror it was that Nicias, the general of the Athenians, being ignorant of the cause, was afraid to lead out the fleet, and brought great distress on his troops. Hail to your genius, ye interpreters of heaven! ye who comprehend the nature of things, and who have discovered a mode of reasoning by which ye have conquered both gods and men! For who is there, in observing these things and seeing the labours which the stars are compelled to undergo (since we have chosen to apply this term to them), that would not cheerfully submit to his fate, as one born to die? I shall now, in a brief and summary manner, touch on those points in which we are agreed, giving the reasons where it is necessary to do so; for this is not a work of profound argument, nor is it less wonderful to be able to suggest a probable cause for everything, than to give a complete account of a few of them only.

Pliny, Natural History. Book II, Chapter 10. On the Recurrence of the Eclipses of the Sun and Moon

It is ascertained that the eclipses complete their whole revolution in the space of 223 months, that the eclipse of the sun takes place only at the conclusion or the commencement of a lunation, which is termed conjunction, while an eclipse of the moon takes place only when she is at the full, and is always a little farther advanced than the preceding eclipse. Now there are eclipses of both these stars in every year, which take place below the earth, at stated days and hours; and when they are above it they are not always visible, sometimes on account of the clouds, but more frequently, from the globe of the earth being opposed to the vault of the heavens. It was discovered two hundred years ago, by the sagacity of Hipparchus, that the moon is sometimes eclipsed after an interval of five months, and the sun after an interval of seven; also, that he becomes invisible, while above the horizon, twice in every thirty days, but that this is seen in different places at different times. But the most wonderful circumstance is, that while it is admitted that the moon is darkened by the shadow of the earth, this occurs at one time on its western, and at another time on its eastern side. And farther, that although, after the rising of the sun, that darkening shadow ought to be below the earth, yet it has once happened, that the moon has been eclipsed in the west, while both the luminaries have been above the horizon. And as to their both being invisible in the space of fifteen days, this very thing happened while the Vespasians were emperors, the father being consul for the third time, and the son for the second.

Pliny, Natural History. Book II, Chapter 11. Of the Motion of the Moon

It is certain that the moon, having her horns always turned from the sun, when she is waxing, looks towards the east; when she is waning, towards the west. Also, that, from the second day after the change, she adds 47-1/2 minutes each day, until she is full, and again decreases at the same rate, and that she always becomes invisible when she is within 14 degrees of the sun. This is an argument of the greater size of the planets than of the moon, since these emerge when they are at the distance of 7 degrees only. But their altitude causes them to appear much smaller, as we observe that, during the day, the brightness of the sun prevents those bodies from being seen which are fixed in the firmament, although they shine then as well as in the night: that this is the case is proved by eclipses, and by descending into very deep wells.

Pliny, Natural History. Book II, Chapter 12. Of the Motions of the Planets and the General Laws of their Aspects

The three planets, which, as we have said, are situated above the sun, are visible when they come into conjunction with him. They rise visibly in the morning, when they are not more than 11 degrees from the sun; they are afterwards directed by the contact of his rays, and when they attain the trine aspect, at the distance of 120 degrees, they take their morning stationary positions, which are termed primary; afterwards, when they are in opposition to the sun, they rise at the distance of 180 degrees from him. And again advancing on the other side to the 120th degree, they attain their evening stations, which are termed secondary, until the sun having arrived within 12 degrees of them, what is called their evening setting becomes no longer visible. Mars, as being nearer to the sun, feels the influence of his rays in the quadrature, at the distance of 90 degrees, whence that motion receives its name, being termed, from the two risings, respectively the first and the second nonagenarian. This planet passes from one station to another in six months, or is two months in each sign; the two other planets do not spend more than four months in passing from station to station.

The two inferior planets are, in like manner, concealed in their evening conjunction, and, when they have left the sun, they rise in the morning the same number of degrees distant from him. After having arrived at their point of greatest elongation, they then follow the sun, and having overtaken him at their morning setting, they become invisible and pass beyond him. They then rise in the evening, at the distances which were mentioned above. After this they return back to the sun and are concealed in their evening setting. The star Venus becomes stationary when at its two points of greatest elongation, that of the morning and of the evening, according to their respective risings. The stationary points of Mercury are so very brief, that they cannot be correctly observed.

Pliny, Natural History. Book II, Chapter 13. Why the Same Stars Appear at Some Times More Lofty and at Other Times More Near

The above is an account of the aspects and the occultations of the planets, a subject which is rendered very complicated by their motions, and is involved in much that is wonderful; especially, when we observe that they change their size and colour, and that the same stars at one time approach the north, and then go to the south, and are now seen near the earth, and then suddenly approach the heavens. If on this subject I deliver opinions different from my predecessors, I acknowledge that I am indebted for them to those individuals who first pointed out to us the proper mode of inquiry; let no one then ever despair of benefiting future ages.

But these things depend upon many different causes. The first cause is the nature of the circles described by the stars, which the Greeks term “apsides”, for we are obliged to use Greek terms. Now each of the planets has its own circle, and this a different one from that of the world; because the earth is placed in the centre of the heavens, with respect to the two extremities, which are called the poles, and also in that of the zodiac, which is situated obliquely between them. And all these things are made evident by the infallible results which we obtain by the use of the compasses. Hence the apsides of the planets have each of them different centres, and consequently they have different orbits and motions, since it necessarily follows, that the interior apsides are the shortest.

The apsides which are the highest from the centre of the earth are, for Saturn, when he is in Scorpio, for Jupiter in Virgo, for Mars in Leo, for the Sun in Gemini, for Venus in Sagittarius, and for Mercury in Capricorn, each of them in the middle of these signs; while in the opposite signs, they are the lowest and nearest to the centre of the earth. Hence it is that they appear to move more slowly when they are carried along the highest circuit; not that their actual motions are accelerated or retarded, these being fixed and determinate for each of them; but because it necessarily follows, that lines drawn from the highest apsis must approach nearer to each other at the centre, like the spokes of a wheel; and that the same motion seems to be at one time greater, and at another time less, according to the distance from the centre.

Another cause of the altitudes of the planets is, that their highest apsides, with relation to their own centres, are in different signs from those mentioned above. Saturn is in the 20th degree of Libra, Jupiter in the 15th of Cancer, Mars in the 28th of Capricorn, the Sun in the 19th of Aries, Venus in the 27th of Pisces, Mercury in the 15th of Virgo, and the Moon in the 3rd of Taurus.

The third cause of the altitude depends on the form of the heavens, not on that of the orbits; the stars appearing to the eye to mount up and to descend through the depth of the air. With this cause is connected that which depends on the latitude of the planets and the obliquity of the zodiac. It is through this belt that the stars which I have spoken of are carried, nor is there any part of the world habitable, except what lies under it; the remainder, which is at the poles, being in a wild desert state. The planet Venus alone exceeds it by 2 degrees, which we may suppose to be the cause why some animals are produced even in these desert regions of the earth. The moon also wanders the whole breadth of the zodiac, but never exceeds it. Next to these the planet Mercury moves through the greatest space; yet out of the 12 degrees (for there are so many degrees of latitude in the zodiac), it does not pass through more than 8, nor does it go equally through these, 2 of them being in the middle of the zodiac, 4 in the upper part, and 2 in the lower part. Next to these the Sun is carried through the middle of the zodiac, winding unequally through the two parts of his tortuous circuit. The star Mars occupies the four middle degrees; Jupiter the middle degree and the two above it; Saturn, like the sun, occupies two. The above is an account of the latitudes as they descend to the south or ascend to the north. Hence it is plain that the generality of persons are mistaken in supposing the third cause of the apparent altitude to depend on the stars rising from the earth and climbing up the heavens. But to refute this opinion it is necessary to consider the subject with very great minuteness, and to embrace all the causes.

It is generally admitted, that the stars, at the time of their evening setting, are nearest to the earth, both with respect to latitude and altitude, that they are at the commencement of both at their morning risings, and that they become stationary at the middle points of their latitudes, what are called the ecliptics. It is, moreover, acknowledged, that their motion is increased when they are in the vicinity of the earth, and diminished when they are removed to a greater altitude; a point which is most clearly proved by the different altitudes of the moon. There is no doubt that it is also increased at the morning risings, and that the three superior planets are retarded, as they advance from the first station to the second. And since this is the case, it is evident, that the latitudes are increased from the time of their morning risings, since the motions afterwards appear to receive less addition; but they gain their altitude in the first station, since the rate of their motion then begins to diminish, and the stars to recede.

And the reason of this must be particularly set forth. When the planets are struck by the rays of the sun, in the situation which I have described, i.e. in their quadrature, they are prevented from holding on their straight forward course, and are raised on high by the force of the fire. This cannot be immediately perceived by the eye, and therefore they seem to be stationary, and hence the term station is derived. Afterwards the violence of the rays increases, and the vapour being beaten back forces them to recede.

This exists in a greater degree in their evening risings, the sun being then turned entirely from them, when they are drawn into the highest apsides; and they are then the least visible, since they are at their greatest altitude and are carried along with the least motion, as much less indeed as this takes place in the highest signs of the apsides. At the time of the evening rising the latitude decreases and becomes less as the motion is diminished, and it does not increase again until they arrive at the second station, when the altitude is also diminished; the sun’s rays then coming from the other side, the same force now therefore propels them towards the earth which before raised them into the heavens, from their former triangular aspect. So different is the effect whether the rays strike the planets from below or come to them from above. And all these circumstances produce much more effect when they occur in the evening setting. This is the doctrine of the superior planets; that of the others is more difficult, and has never been laid down by any one before me.

Pliny, Natural History. Book II, Chapter 14. Why the Same Stars Have Different Motions

I must first state the cause, why the star Venus never recedes from the sun more than 46 degrees, nor Mercury more than 23, while they frequently return to the sun within this distance. As they are situated below the sun, they have both of them their apsides turned in the contrary direction; their orbits are as much below the earth as those of the stars above mentioned are above it, and therefore they cannot recede any farther, since the curve of their apsides has no greater longitude. The extreme parts of their apsides therefore assign the limits to each of them in the same manner, and compensate, as it were, for the small extent of their longitudes, by the great divergence of their latitudes. It may be asked, why do they not always proceed as far as the 46th and the 23rd degrees respectively? They in reality do so, but the theory fails us here. For it would appear that the apsides are themselves moved, as they never pass over the sun. When therefore they have arrived at the extremities of their orbits on either side, the stars are then supposed to have proceeded to their greatest distance; when they have been a certain number of degrees within their orbits, they are then supposed to return more rapidly, since the extreme point in each is the same. And on this account it is that the direction of their motion appears to be changed. For the superior planets are carried along the most quickly in their evening setting, while these move the most slowly; the former are at their greatest distance from the earth when they move the most slowly, the latter when they move the most quickly. The former are accelerated when nearest to the earth, the latter when at the extremity of the circle; in the former the rapidity of the motion begins to diminish at their morning risings, in the latter it begins to increase; the former are retrograde from their morning to their evening station, while Venus is retrograde from the evening to the morning station. She begins to increase her latitude from her morning rising, her altitude follows the sun from her morning station, her motion being the quickest and her altitude the greatest in her morning setting. Her latitude decreases and her altitude diminishes from her evening rising, she becomes retrograde, and at the same time decreases in her altitude from her evening station.

Again, the star Mercury, in the same way, mounts up in both directions from his morning rising, and having followed the sun through a space of 15 degrees, he becomes almost stationary for four days. Presently he diminishes his altitude, and recedes from his evening setting to his morning rising. Mercury and the Moon are the only planets which descend for the same number of days that they ascend. Venus ascends for fifteen days and somewhat more; Saturn and Jupiter descend in twice that number of days, and Mars in four times. So great is the variety of nature! The reason of it is, however, evident; for those planets which are forced up by the vapour of the sun likewise descend with difficulty.

Pliny, Natural History. Book II, Chapter 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, 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; 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. 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.

Pliny, Natural History. Book II, Chapter 16. The Reason Why the Stars are of Different Colors

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; 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, 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 rendering them more feeble than when they fall upon her more directly. 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, 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.

Pliny, Natural History. Book II, Chapter 17. 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, in the 8th degree of Aries and Libra. 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 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.

Pliny, Natural History. Book II, Chapter 18. 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, 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; 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.

Pliny, Natural History. Book II, Chapter 19. 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. 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; and this was also the opinion of our countryman, Gallus Sulpicius.

Pliny, Natural History. Book II, Chapter 20. 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, meaning the whole compass of the notes. In this, Saturn is said to move in the Doric time, Jupiter in the Phrygian, and so forth of the rest; but this is a refinement rather amusing than useful.

Pliny, Natural History. Book II, Chapter 21. Of the Dimensions of the World

The stadium is equal to 125 of our Roman paces, or 625 feet. Posidonius supposes that there is a space of not less than 40 stadia around the earth, whence mists, winds and clouds[263] 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. 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. 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. 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, we have the half of the sum of these numbers. And this is indeed a very modest calculation, since if we add to the orbit of Saturn the distance from him to the zodiac, we shall have an infinite number of degrees.

Pliny, Natural History. Book II, Chapter 22. 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.

The Greeks name these stars “comets”; 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. Those that are named Acontiæ 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; these are the pale kind; they shine like a sword and are without any rays; while we name those Discei, which, being of an amber colour, in conformity with their name, emit a few rays from their margin only. A kind named Pitheus exhibits the figure of a cask, appearing convex and emitting a smoky light. The kind named Cerastias has the appearance of a horn; it is like the one which was visible when the Greeks fought at Salamis. Lampadias is like a burning torch; Hippias 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. The shortest time during which any one of them has been observed to be visible is 7 days, the longest 180 days.

Print Friendly, PDF & Email