On the Apparent Face in the Orb of the Moon

I. Then said Sylla, "These things belong to my story, and form part of it: but if you come at all into collision with these popular notions, that are in everybody's mouth, about the Face in the Moon, I think I should be glad to learn it." "Why should we not," I replied, "driven back as we are by the difficulty in the first case, to the latter subject—just as people in lingering diseases, when they have lost all hope in the common remedies, and usual courses of diet, fly for refuge to purifications, spells, and dreams: in the same way it is a matter of compulsion in obscure and insoluble problems, when common, accredited, and customary arguments fail to convince, to make trial of others more out of the way, and not despise them; but to chant, as it were, over ourselves some old-fashioned charm, and hunt out the truth in all quarters. II. "For you see at once how absurd is the explanation that the apparent figure in the moon is merely an affection of the sight, which is dazzled by the brightness, by reason of its own weakness; a thing we call … it 1 takes no notice that this effect should rather take place in regard p. 198 to the Sun, which strikes upon the eye both sharp and forcibly; whence Empedocles hath described the difference between the two, not inelegantly,

to the Sun, which strikes upon the eye both sharp and forcibly; whence Empedocles hath described the difference between the two, not inelegantly, "The shrill-voiced sun, the softly whispering moon,' designating in this way the attractive, cheerful, and inoffensive character of the latter luminary. Afterwards, giving the reason why dim and weak eyes discern no difference of form in the moon, but her orb strikes upon them as smooth and completely filled up, whilst those that have sharp and strong sight make out better, and distinguish the lineaments of the Face, and seize upon the difference more clearly. For the contrary ought to be the case, if that appearance were produced from the eye's being overcome; because where the sense affected was weaker, the stronger 1 would be the impression produced. But the inequality [of the surface] refutes this explanation, for the sight does not rest upon a continuous and confused shadow. And Hegesianax in describing it hath not ill said, "'With fire she shines all round, but in the midst More blue than black appears a maiden's face And moisten’d 2 cheeks, that blush to meet the gaze.' [paragraph continues] For in reality the shaded parts, as they go round, creep under the bright ones, and are in turn cut away and compressed, 3 and in a word, are interwoven one with the other. So that the figure resembles a sketch in outline, 4 according to Clearchus; which seems plausibly said to your Aristotle—for Aristotle is a man of your own, being, as he was, fond

[paragraph continues] For in reality the shaded parts, as they go round, creep under the bright ones, and are in turn cut away and compressed, 3 and in a word, are interwoven one with the other. So that the figure resembles a sketch in outline, 4 according to Clearchus; which seems plausibly said to your Aristotle—for Aristotle is a man of your own, being, as he was, fond p. 199 of antiquity, although he did introduce into it a good deal of the Peripatetic philosophy. III. And upon Apollonius taking up the conversation, and asking what was the opinion of Clearchus: "It better suits," replied I, "any other person than yourself to be ignorant of the story, inasmuch as it proceeds from the very focus of geometry: for the fellow says that the so-called face is only reflected images and appearances of the great sea (the ocean) that are shown upon the moon; for that her external circumference when concave 1 is naturally adapted to catch the reflections rising up from various quarters, whilst the full moon is of all mirrors, in point of polish and of brilliancy the most beautiful and the most clear. For just as you suppose that the rainbow, when the light is reflected against the sun, is impressed upon the clouds that have received gradually a watery smoothness and surface, in the same way, that writer says, the external sea (our ocean) is reflected on the moon, not indeed from the place it occupies, but from where the reflection of the air has made the image of it, that is to say, its surface and reflection. And Agesianax, in another place, has said:—

"'Or some great wave of ocean, rising steep, Shows like an image on the blazing mirror."' IV. Apollonius then was amused, and exclaimed: "How original and entirely new is the construction of this theory—it bespeaks a man possessed of audacity as well as wit! But in what way is it open to objection?" "In the first place," I replied, "because the nature of the outer sea is one and the same, a uniform and unbroken expanse of water; whereas the appearance of the dark parts in the moon is not one and the same, but shows as it were projecting tongues of land, because the bright part diversifies p. 200 and defines the dark; so that from each of these being separated, and having a boundary of its own, the projections of the bright parts upon the darkened, assuming the form of elevations and depressions, arrange in a most natural manner the features that appear around the eyes and lips; so that we must either suppose there are several outer seas intersected by tongues of land and continents, which supposition is both absurd and false, or else there being but one it is not reasonable that the image of it should be reflected diversified in this way. It is, however, safer to ask the question than to demonstrate, when you are present, whether the habitable world, being equal in length and width, it is possible for all the view at once from the moon to be reflected and reach the sea… nay, more, to such as are sailing on the great ocean, and live in the middle of it, like the Britons—and this too, whilst the earth, as you have told us, does not occupy the place of a centre with regard to the sphere of the moon." 1 "It is your business," I replied, "to investigate this problem; the reflection of the prospect, however, against the moon, is neither your business to investigate, nor that of Hipparchus, although it is an interesting question. But many amongst natural philosophers are not satisfied to hold this doctrine of similar effects with respect to the sight; but it is more probable that the thing is a collision, or as it were impact and rebound of particles, in the same way as the atoms invented by Epicurus. Your Clearchus will not, I fancy, suppose the moon a ponderous and solid body, but a star composed of æther, and luminous, to use your language, … it is natural she should reflect the view or the impact to the same extent that the reflection has gone away from her. And if he requires anything more, we will ask how it comes that the face in the moon alone is

p. 201 the reflection of the ocean, and not in any other of the stars, numerous as they be: and yet probability demands that the sight should be thus affected with respect to all alike, or no one at all. Look at Lucius, and remind him of what was said at first starting." V. Then Lucius: "But for fear we should seem to be insulting Pharnaces, by passing over the Stoical doctrine on the subject, without a word said for it, pray make some reply, by all means, to the man that supposes the moon a mixture of air and liquid fire, and asserts that as when a ripple runs over the sea in a calm, so when this air blackens, an appearance like definite shapes is produced … [on the moon's face]." "You act kindly," replied I, "my dear Lucius, in thus cloaking their absurdity under decent names; but not so did our friend, who used to say, 'they gave the moon a black eye,' by thus covering her face with spots and dark patches, at one and the same time proclaiming her Artemis and Athene, and then making her out a composition and mass of dusky air and coaly fire, not possessing any kindling spark or light of her own, but to be a body hard of separation, and scorched by fire: just like those pieces of earthenware styled by the poets 1 'lustreless and ashy.' Because, however, a charcoal fire, such as they make out the moon's to be, has neither permanence nor consistence, unless it gets hold of a material that retains and at the same time feeds it, I fancy those philosophers have seen farthest into the matter who say in joke, that Vulcan is said to be lame, because fire cannot go on without wood any more than a lame man without a stick. If, then, the moon is fire, from whence is so large a quantity of air generated in her? for the region that revolves

p. 202 above and around her is not of air, but of a superior element, that has the natural property of sublimating and setting on fire everything in its reach. And if this air has been generated, how comes it that it continues so long a time, and does not fly off and change its form, being set at liberty by the fire, but maintains itself and co-exists such a length of time together with the fire, like a nail fixed in the same place and riveted close? For it behoves it, as being subtile and diffused, not to remain stationary, but to fly abroad; for that it should be condensed is not possible, inasmuch as it is mixed up with fire, and has no particle of moisture nor of earth, by which things alone are as naturally disposed to be solidified. And velocity of flight inflames the air contained in stones and in that cold substance, lead, 1 much more, then, that contained in fire, whirling along too with such immense swiftness. For they (the Stoics) quarrel with Empedocles for making the moon 'a congelation of air, of the nature of hail, embraced by a sphere of fire;' whilst they themselves pretend that the moon, a ball of fire, contains air dispersed in different directions, and this, too, though she has neither fissures in her surface, nor deep places, nor cavities (things which those that make her out an earthly substance concede to her), but this same air is lying, forsooth, superficially upon her convexity. This arrangement is preposterous with respect to permanence, 2 and impossible with respect to sight in the times of full moon; for, in that case, it ought not to define anything black and shaded, but either be hidden and darkened [completely], or else to be lighted up at the same time when the moon is taken possession of by the

p. 203 sun. For amongst ourselves, the air in the deep places and hollows of the earth, whither the light doth not enter, continues obscure and unilluminated; whilst that from without diffused around the earth acquires brightness and a lustrous colour, for it readily mixes itself with every kind of property, or force, by reason of its liquid nature, and especially if it but 'lay hold of the light,' as you call it, and touch the same, then is it entirely converted and lighted up. This selfsame fact, therefore, though it may seem to do good service to such as are for thrusting the air in the moon into her deep places and ravines, yet refutes those of you who knead up and compose her sphere, I know not how, out of air and fire; for it is not possible for shade to be left upon her surface, when the sun illuminates with his light the whole extent of the moon that we take in with the sight." VI. Then Pharnaces, whilst I was still speaking, broke in with: "Just what I expected conies against us, borrowed from the Academy, when we are engaged in arguing with other people: never to furnish proof of what they assert themselves, but they needs must treat as defendants such as do not attack them, whatever the case maybe. But me, at any rate, you will not draw into making a defence of the theory you impute to the Stoics, before I get satisfaction out of you for turning the affairs of the universe upside down." "Only," replied Lucius laughing, "do not bring an action for impiety against us, just as Cleanthes thought it right that the Greeks collectively should impeach Aristagoras 1 the Stoic, of impiety, for overthrowing the altar of earth, because the fellow attempted to account for visible phenomena by supposing that the sky remains fixed, and that the earth rolls round down an oblique circle, 2 turning at

p. 204 the same time upon its own axis. We, however, say nothing out of our own heads; whilst they who suppose the moon an earth, how do they turn things upside down, any more than you do who place the earth here in the air, although it be, by far, bigger than the moon, as mathematicians calculate her magnitude during her eclipses, and by the length of time 1 consumed in her passage through the shadow? For the shadow of the earth is projected of lesser size by the illuminating body being the larger; and that the upper part of the shadow itself is fine and narrow, was not unknown, as he says, to Homer also, for he entitles night 'swift,' 2 by reason of the pointed form of the shadow. But by this philosopher the moon is convicted on the strength of her eclipses, and gets off with hardly three of her own (apparent) magnitudes, for consider to how many moons the earth is equal, if it projects a shadow, which, al the shortest, is thrice the diameter of the moon. But yet you are afraid for the moon, lest she should tumble down; but as for the earth, Eschylus perhaps has reassured you, like Atlas, "'He stands, the pillar of the sky and earth, Propping a load not easy for the arms;' that is, if there flows under the moon only thin air, not competent to support a solid body; whilst the earth, according to Pindar, 'adamantine-shod columns keep in on every side.' And for this reason Pharnaces himself is under no apprehension of the earth's falling, whereas he

that is, if there flows under the moon only thin air, not competent to support a solid body; whilst the earth, according to Pindar, 'adamantine-shod columns keep in on every side.' And for this reason Pharnaces himself is under no apprehension of the earth's falling, whereas he p. 205 compassionates such as lie under the roadway of the moon, namely, the Ethiopians and people of Taprobane, lest so vast a weight should drop upon them; and yet, a safeguard to the moon against falling down is her motion, and the rapidity 1 of her gyration, just as objects placed in slings have a hindrance from falling out in the circular whirling. For the natural tendency acts upon each object, unless it be diverted by some extraneous force. Consequently, her own weight does not act upon the moon, because by means of her rapid rotation its downward tendency is neutralized; there were rather cause to wonder at her not remaining stationary, like the earth, and not rolling out of her place. As it is, the moon has the greatest reason for not being carried in our direction; but the earth, as being destitute of other motion, it was natural should remain fixed through the force of gravity alone, because it is heavier than the moon, not by the same proportion as it is the larger of the two, but in still greater degree inasmuch as the latter is all the lighter through heat and burning up of her substance. And, in fine, the moon, from what you say, if she be fire, naturally stands in need of earth and matter, in which she walks, and clings to, and keeps together, and fans the flame of her force. Now fire cannot be imagined as being maintained without fuel, but earth, you assert, remains fixed without either foundation or root." "Certainly so," replied Pharnaces, "because it occupies its proper and natural place, as being itself the centre, for this is the place around which all weights gravitate and rest, and are carried and tend together from all parts; whereas the whole upper region, even though it should receive some earthy substance forcibly thrown up, immediately excludes it—better say, discharges it, to be carried downwards in the way its own natural tendency directs."

VII. In return for this, I wishing to obtain a little respite p. 206 for Lucius whilst refreshing his memory, called to Theon: "Who was it, Theon," said I, "of the tragic writers that remarks of physicians that, "'With bitter drugs they purge the bitter bile?" and on his answering, "Sophocles," "This privilege must be granted to them," said I, "whether we will or no; but we must not listen to philosophers when they choose to defend absurdities by other absurdities, and in fighting for the monstrosities of their doctrines invent others yet more strange and wonderful, just as these men bring in the gravitation to the centre'—a notion, what amount of extravagance does it not involve? Do not they make out earth to be a sphere, though it contains such depths and heights and inequalities of surface? Do not they make the Antipodes live like caterpillars or lizards, turned upside down, clinging to the earth? And they represent ourselves as not walking erect to stand firm upon it, but wavering away all on one side, like so many drunken men! Don't they pretend that masses of a thousand talents weight falling through the depths of earth, when they arrive at the centre are arrested, though there be nothing to encounter or support them? and that if, carried along by their velocity, they shoot past the centre, they are turned back again and retrace their course spontaneously? Do not they teach that sections of beams, sawed off on each side of earth, 1 do not tend downwards continually, but when they fall upon the ground 2 are repelled from without, and are come together again at the centre, 3 and that

p. 207 an impetuous stream of water flowing downwards, should it come to the central point (which they pretend is incorporeal) stands fast suspended in a circle around the pole, incessantly lifting up, and being lifted up incessantly? Some of these notions, indeed, they do not assert without foundation, if one should strain himself to the utmost to present them to his conception. This is indeed turning things upside down and making them run backwards, to make as far as the centre 'downwards,' and under the centre 'upwards.' So that if a person out of sympathy for the earth, should occupy the centre thereof, and should stand upon his head, holding at the same time his head upwards and his feet also, 1 and dig through all the space opposite him, he would emerge turned upside down and be dragged along on coming to the surface; and if forsooth, another man be imagined as walking opposite to him the feet of both would be, and also be called, turned 'upwards.' VIII. "Of such and such great absurdities not a walletful, but rather a whole juggler's stock and shopful, have these men strapped upon their backs and drag after them, and yet they say others are idle chatterers for placing the moon, being an earth, up aloft, not where the centre is. And yet truly, if every ponderous thing does tend towards the same point, and presses with all its particles upon its own centre—earth will claim for herself all ponderous things, not so much because earth is the centre of the universe, as because they are particles of herself; and the fact of things gravitating downwards will be a proof, not of the centripetal force towards earth, but of affinity and sympathy, as it were, with earth, in particles once separated from her, and now flying back to her again. For in the same way that the sun attracts to himself the

p. 208 particles out of which he is composed, so doth earth receive the falling stone, and carries it to the place where in course of time each one of such bodies is made one with and assimilated to herself. But if it happens to be some other body, not assigned to earth from the beginning, nor a fragment separated from herself, but having a composition and nature of its own (as those men will say of the moon)—what prevents it from existing by itself, separately, following its own tendency, and fettered by its own particles? By no means is earth proved to be the centre of the universe, and the connection and relation of the latter here with earth, guide us to the manner in which it is probable the phenomena relating to the moon take their course. I do not see why the philosopher who forces all earthy and ponderous particles into one and the same place, and makes them out portions of one and the same body, does not concede the same natural tendency to such as are without weight, but allows so many composite bodies of fire to exist separately, and does not imperatively collect into one lump all the stars that be, and demand that there should be one common body of all upward tending and fiery particles." IX. "But," said I, "you assert that the sun, my dear Apollonides, is distant infinite myriads of miles from the superior circumference, while the Morning Star, and Mercury, and the other planets, all placed below him, keeping far aloof from the fixed stars, and at great distances from each other, pursue their course; 1 whereas for the ponderous and earthy particles you suppose the universe offers no free space, nor interval between each other in its whole extent. You see it is ridiculous if we shall assert that the moon is not an earth because she is posted remote from the lower space, but should call her a star, seeing her

p. 209 thrust away so many myriads of miles from the superior circumference, and crept as it were into some hole and corner of creation: at least she is so much below the other stars that one cannot express the measure of the distance, but arithmetic fails you mathematicians in calculating the same; whereas, in a manner, she touches Earth, and revolving near, "'As of a chariot, follows in the rut,' says Empedocles. 'She around the point …' "For neither does she often overpass the shadow [of Earth], and elevate herself a little, by reason that the illuminating body is exceeding great, but she appears to revolve so close to, and as it were in the embrace of Earth, as to be screened against the Sun by it, without ever soaring above this shady terrestrial and darksome region which is the allotment of Earth. Wherefore I think we must confidently declare the moon to be within the limits of Earth, and to be overcast by the point of Earth's shadow. 1 X. "And consider, leaving out of the case the other fixed stars and planets, what Aristarchus points out in his treatise 'Upon Magnitudes and Distances,' that the distance of the sun is more than eighteen times, but less than twenty times the distance of the moon, by which she is separated from us: and yet the computation that gives the greatest elevation to the moon says she is distant from us fifty-six times the space from the centre of the earth [to the circumference]: 2 this length is of forty thousand 3

p. 210 stadia, according to those who make a moderate calculation of it. And, calculated from this basis, the sun's distance from the moon amounts to over four thousand and thirty myriads of stadia. So far, then, is she separated from the sun by reason of her weight, and approximated to earth, that if one must define substances by localities, the constitution and beauty of Earth attracts the moon, and she is of influence in matters and over persons upon Earth, by reason of her relationship and proximity. And we do not go wrong, I think, when we assign to those bodies above denominated such immense depth and distance, and leave to that which is below a certain circular course and broadway as much as lies between earth and the moon: for neither the man who pretends the summit of heaven to be the sole 'above,' and denominates all the rest as 'below,' is reasonable in his definition; nor yet is he who circumscribes 'below' by the limits of Earth, or rather by the Centre, to be listened to: but even moveable … inasmuch as the universe allows of the interval required by reason of its own extensiveness. But in reply to such as demand that all which is separate from earth shall be consequently 'above' and 'on high,' another directly responds with the contrary axiom, that all which is reckoned from the fixed circumference is to be considered as 'below.' XI. "And, finally, in what sense, and in reference to what thing is Earth said to be 'intermediate?' For the universe is infinite; now that which is infinite hath neither beginning nor limit, so it does not belong to it to possess a middle: for infinity is the deprivation of limits. But he who makes out Earth to be the middle not of the universe, but of the world, is ridiculous for his simplicity if he does not reflect that the world' itself is liable to the very same objections: for the universe hath not left a middle place for it also, but it is borne along without house or

p. 211 home in the boundless vacuum, towards nothing cognate to itself; perhaps it has found out for itself some other cause for remaining fixed, and so has stood still, but certainly not owing to the nature of its position. And it is allowable for one to conjecture alike with respect to Earth and with respect to the moon, that by some contrary soul and nature they are 1 …, differences, the former remaining stationary here, the latter moving along. But apart from these considerations, see whether a certain important fact has not escaped their notice. For if whatsoever space, and whatever thing exists away from the centre of Earth, is the 'above,' then no part of Earth is 'below,' but Earth herself and the things upon Earth; and, in a word, everybody standing around or investing the centre, become the 'above;' whilst 'below' is one sole thing, that incorporeal point, which has the duty of counterbalancing the whole constitution of the world; if, indeed, the 'below' is by its nature opposed to the 'above.' And this is not the only absurdity in the argument, but it also does away with the cause through which all ponderous bodies gravitate in this direction, and tend downwards: for there is no mark below towards which they move: for the incorporeal point is not likely (nor do they pretend it is) to exert so much force as to draw down all objects to itself, and keep them together around itself. But yet, it is proved unreasonable, and repugnant to facts, to suppose the 'above' of the world to be a whole, but the 'below' an incorporeal and indefinite limit: whereas that course is consistent with reason, to say, as we do, that the space is large and possessed of width, and is defined by the 'above' and the 'below' of locality.

XII. "Not but that we may, if you please, suppose that motions in the heavens are contrary to the nature of those of terrestrial bodies; and let us examine the matter quietly, p. 212 not in the tragic style, but in a good-humoured way, how such an assumption as this does not make out the moon not to be an earth, but only an earth in a position for which it is not naturally adapted. For the phenomena at Etna underground are against the order of Nature; but 'fire is there, and the blast imprisoned in the bellows is the upward force;' 1 whereas that which by nature is imponderous, comes, in spite of itself, into places for which it was not made. And the Soul itself," I continued, "is it not locked up by God in the body against its own nature: the one swift, the other slow; the one fiery, the other frigid (as you assert); the one invisible, the other an object of sense? For this reason, therefore, let us not say that the soul is nothing to the body; but that it is a thing divine, which by reason of its gravity and density, travels round all heaven, earth, and sea, at one and the same moment, and being parcelled out pervades the flesh, the sinews, the marrow of our bodies, the cause of feelings in infinite variety, when coupled with moisture. But this Jupiter of ours doth not follow his own nature, nor is one great continuous fire; but occasionally he withdraws himself, bends downwards, and changes his form, having turned and still turning himself into every object in the course of his changes. But take heed, my good sir, and consider, lest by transposing and drawing away each thing in turn from the place where it is naturally meant to be, you philosophically bring about the dissolution of the world, and introduce the 'Discord' of Empedocles into its affairs; or, rather, lest you stir up to war upon Nature, the Titans and Giants of old, and should desire to see again the fabled terrific disorder and lawlessness of their times; apart everything ponderous, and apart everything light:

"'Where no one views with awe Sol's glorious face, Nor Earth's own shaggy breed, nor Ocean's kind,' p. 213 as Empedocles says; nor did Earth participate in heat, nor Water in air, neither was there anything of the ponderous up above, or of the imponderous down below, but unmixed, unsocial, solitary were the principles of the universe—not admitting the union of one with another, nor communication, but fleeing and shrinking away from each other, carried along by individual and independent impulses, they were so circumstanced as is everything from which God is absent, according to Plato (that is, just as our bodies are circumstanced, when mind and soul have left them); until what time Desire came upon Nature by the sending of Providence, when Amity was engendered, and Venus and Love, as Empedocles declares, as also say Parmenides and Hesiod, in order that they, by exchanging places and borrowing forces from one another, and the one set being bound by the necessity of motion, the other by that of rest, compelled to emerge and change pace from the position where Nature placed them, towards a better one, they might bring about the union and fellowship of the Whole. XIII. "For if no other part of the divisions of the world were placed contrary to its nature, but each lay where it was naturally fit, standing in need of no change of place nor re-arrangement, and without having needed anything of the sort at the beginning, I am puzzled to see what is the business of a Providence, or of what Jupiter has been creator and father, 'that most skilful artificer.' For there is no use of marshallers in a camp, if each one of the officers knows out of his own head the rank, station, and moment, that he is bound to occupy and to observe; nor of gardeners or builders, if the water of itself is disposed to move upon the things that require it, and to flow over and irrigate the same; and in the other case, the bricks, timbers, and stones following their natural tendencies and inclinations, should of themselves

p. 214 take up the requisite arrangement and position. And if this argument does not downright subvert the doctrine of a Providence, but leaves to God the government and distribution of things that be—why should we be surprised that Nature has been so ordered and divided, that here is fixed Fire, there Stars; and again, the Earth here, and overhead the Moon; all of them bound by a stronger chain than the natural one, that is, by the one in accordance with Reason? 1 Wherefore, if all things must needs follow their natural tendencies, and move on in the manner for which they were created, then let not the Sun revolve in a circle, nor yet Venus, nor any other of the planets, do the same—for it is upward, and not in a circle, that imponderous and fiery bodies were created to move. But if Nature possesses such a power of exchange, in spite of the locality, 2 that here Fire as it moves, moves upwards, but after it has arrived at heaven, it is carried around in company with the celestial revolution. What is there to be surprised at if it comes to pass with ponderous and earthy bodies, when transferred into another form of motion, that they be overpowered by the influence of the element that encompasses them? For in fact, it is not consistent with Nature that the upward tendency of imponderous bodies should be neutralized by the motion of the heavens; but rather that it should not be able to master such as be ponderous and gravitate downwards; nay rather, on occasion, when it has transposed the latter also by its own power, it should employ their nature to a better end than for what it was created.

XIV. "Not but that if one must dismiss the notion of habits violently overcome, and speak one's opinion without disguise, it is probable no part of the universe possesses either place, order, or motion, of its own, which we can universally style its natural one; but that when each p. 215 thing shows itself usefully and properly moving to that end on account of which, and for which, it was born or has been manufactured, and submitting to, or doing that which is conducive to its own preservation, perfection, or efficiency, it then appears to possess its natural place, motion, and disposition. Man himself, at any rate, who as much as anything that exists is naturally made, holds upward the ponderous and earthy portions of himself, especially about the head, and in his centre the hot and fiery particles. And of the teeth, part are planted above, part below, and yet neither set are placed contrary to Nature; nor of Fire, is the part that shines in the eyes placed according to nature, and that detached in the belly and the heart placed contrary to nature; but each respectively is stationed properly and serviceably: "'Truly the snail and thick-skinned tortoise,' and the nature of every shell-fish, as Empedocles says from his own observation: "'Where earth thou shalt behold above their flesh,' and the stony substance does not oppress their constitution, nor crush it by its incumbent weight; neither, on the other hand, doth the heat, by reason of its lightness, fly off and escape upwards; but they are mingled with each other and ranged together, in accordance with the nature of each.

and the stony substance does not oppress their constitution, nor crush it by its incumbent weight; neither, on the other hand, doth the heat, by reason of its lightness, fly off and escape upwards; but they are mingled with each other and ranged together, in accordance with the nature of each. XV. "In the same way, therefore, is it probable the world is constituted, that is, if it be a living thing, containing earth in many places, in many others water and fire, and air, not forcibly compressed, but arranged in order by Reason. 1 For neither is the eye squeezed out of the mass p. 216 into the place it now fills in the body, in consequence of its levity, nor did the heart slip down and fall into the breast by reason of its weight, but because it was better each of the two should be so placed. Therefore, let us not think, of the parts of the world, either that Earth is lying here because she hath tumbled down through her own weight, or the Sun (as Metrodorus the Chian supposed) was shot up into the upper region, through his levity, after the manner of a bubble, or that the other stars got into the places where they now are, because they gravitated thither as though according to the discrimination of a pair of scales. 1 But, inasmuch as He that rules by reason is the master, they, like light-giving eyes, are fixed in the brow of the universe, and stray about: whilst the sun fills the place of a heart, and, like blood and breath, distributes and disperses from out of himself both heat and light. Earth and sea the world uses according to Nature for whatever purposes an animal uses its belly and bladder: whilst the moon placed between Heaven and Earth, like the liver between the belly and the heart, or some other soft intestine, diffuses here the warmth from above, and the exhalations rising hence she subtilizes by a certain process of digestion and purification, around herself, and emits them again. But whether her earthy and solid part contains any region adapted for the reception of other things, is a matter we cannot ascertain. And in every case, the better part masters the subordinate part. And what can we gain, so consistent with probability as this, out of what those philosophers assert? They assert that the luminous and subtile part of the æther, was converted into sky by reason of its liquidity; and the condensed and conglomerated part into air, and that the moon is the most sluggish part of these two, and also the most turbid. But in spite of this, it is in anybody's power to see that the moon is not cut off from

p. 217 the æther, but rather floats on much of it in the space around herself, and having under her the wind in abundance … revolve the comets. Thus, each one is put in its fold,' not in accordance with their tendencies depending on the gravity or levity of substance, but as having been arranged by another cause, namely Reason." XVI. After these things had been said, and I banded over the subject to Lucius, as I was advancing to the proofs of the theory, Aristotle said with a smile: "I testify that you have been directing your whole argument against such as suppose the moon to be half made of fire, and who pretend that universally some bodies tend upwards, others downwards, of their own accord. For if there is anyone that says the stars revolve in a circle by their own nature, and are made of an element entirely different from the four we know—something has just occurred to my recollection very opportunely to get them out of the difficulty." "But," said Lucius, "if we make all the other stars, and the whole of heaven, into one pure and unmixed nature, freed also from all necessity of change consequent upon passiveness, and if we trace out an orbit along which they all [shall move] with never-ceasing revolution—no one, perhaps, will quarrel with us on the present occasion; although a thousand difficulties are left still unsolved. And when the argument shall comprehend and touch upon the moon, she no longer keeps her impassiveness, and that vaunted beauty of her substance. But to pass over the other inequalities and differences [she exhibits], this very Face that appears in her, is produced either by seine affection of her own substance, or by the admixture of some different one. Now that which is mixed with another suffers something, for it loses its own purity, being infected by the quality of the inferior element. But her own spurious nature, the weakness of her pace, her heat so inefficient and dull, whereby, according to Ion, 'no grape is ripened black'—to

p. 218 what shall we attribute all this except to her feeble nature and passiveness; that is, if passiveness belongs to an eternal and celestial body? and, to sum up, my dear Aristotle, considered as an Earth the moon shows herself to be a perfectly beautiful, awful, and well-ordered thing; but viewed as a star or a luminary, or some divine and celestial body, I fear she will prove shapeless and uncomely, and bring shame upon that glorious appellation, if of all the so numerous bodies existing in the heavens, she alone goes about begging light from another, according to Parmenides, "'With eyes aye fixed upon the solar beams.'" Now my opponent in the dispute, quoting the saying of Anaxagoras, "The sun grafts brightness in the moon," was applauded by the company; but I will not repeat what I learnt either from you, or conjointly with you; but will gladly go on to what is left. 1 "That the moon, then, is illuminated, not like glass or crystal, by the direct or transmitted light of the sun, is a probable supposition; nor again, by reason of collected illumination or collected reflection, in the same way as torches do, 2 when the light is augmented; for in that ease it will be full moon to us none the less at the times of new moon, or first and third quarters, if she neither covers nor blocks out the sun; but the light rather passes through her by reason of her fluidity, or else it shines into her by way of intermixture, and lights up all around her. For it is not possible to lay the blame in the case of her dark quarters upon her deviations, or retreatings, as in the cases when she shows half her orb, or the same gibbous or crescent-shaped; but, according to Democritus, she stands in a vertical line to the illuminating

p. 219 body, and receives and takes in the sun: so that it were probable that she at the same time is illuminated and illuminates that body. But she is very far from doing this; for at that moment she is invisible, and she frequently hides, and causes him to disappear, 'she strips him of his beams,' as Empedocles says, "'Till up aloft, she veils so much his face As the width measures of the blue-eyed 1 moon:' as though the [sun's] light fell upon night and darkness, and not upon another star. And as to what Posidonius says, that 'the light of the sun does not pass through her, on account of the depth of the moon,' is plainly confuted by the fact; for the air, though unlimited and having a depth many times greater than the moon's, is entirely illuminated and shone upon by his rays. There is left, therefore, the doctrine of Empedocles, that it is by means of a certain reflection of the sun upon the moon that the illumination which proceeds from her here below is brought about. Consequently it [her light] conies to us neither warm, nor brilliant, naturally enough, as there has been a kindling and a mingling of different lights in that case; but just as voices in the case of reflections send back the echo of the sound more dull, and the blows of shots that rebound from an object fall with greatly diminished force, "So the ray striking on the moon's broad disk,' makes a feeble and dull rebound upon us, being deprived of its strength by reflection."

makes a feeble and dull rebound upon us, being deprived of its strength by reflection." XVII. Then Sylla taking up the conversation said: "Certainly, this notion possesses some degree of probability, but the thing that is the strongest of those that p. 220 make against it, pray, does it admit of any softening down, or has it escaped my companion's observation?" "What is this?" replied Lucius, "do you mean the question about the half-moon?" "Yes, certainly," answered Sylla; "for the assertion has some reason on its side, that, since all reflection takes place at equal angles, when the moon, showing but half her disk, rides in mid-heaven, the light from her does not travel towards us, but glides off to the part opposite to earth; for the sun, being upon the horizon, touches the moon with his rays; consequently, being refracted at an equal angle, it [the light from the sun] will rebound to the other extremity, and not throw the light so far as us; or else there will be a great distortion and parallax of the angle, which thing is not possible." "Nay, but indeed," replied Lucius, "this thing has been asserted;" and looking, as he was talking, towards Menelaus the mathematician, "I am ashamed, my dear Menelaus, to take up a mathematical question in your presence, which serves as the very foundation for the whole science of Opticks, but there is no help for it," he continued, "for the fact that all reflection extends itself at equal angles, is neither self-evident nor universally admitted, but is contradicted in the case of convex mirrors, when they make images larger than the objects themselves to one point of vision. It is also contradicted in the case of double mirrors, which being inclined to each other, and an angle formed between them, each of the surfaces presents the appearance of a double one, and gives four images from one face, two of them looking towards the left parts from outside, and two others, indistinct, looking to the right, in the depth of the mirror. Of the production of which images, Plato explains the cause; for he has said that in consequence of the mirror's having got height, 1 on this side and

p. 221 on that, the eyes transfer the reflection, as they change their place from one side to the other. If, therefore, of the images some run back directly to us, whilst some slipping to the other side of the mirror are thrown back again from thence to us, it is not possible that all reflections take place in equal angles, as many as … joining battle, they demand to do away with the equality of angles by means of the emanations flowing from the moon upon the earth, because they suppose this theory more plausible than the former. Not but that if we must needs gratify your great darling, Geometry, and concede the Point,—in the first place it is likely enough that such happens 1 in the case of reflectors made very exact as to their polished surfaces; whereas the moon offers many inequalities and asperities of surface, so that rays from a great body [like the sun] going astray at considerable elevations, that allow of their reflecting and exchanging with one another, are reflected in all sorts of ways, and entangled with each other, and kindle up the lustre in itself, 2 because it is thrown upon us from several reflectors at once. In the next place, even though we allow the reflections upon the moon herself to be at equal angles, it is not impossible that the rays, travelling through so vast a distance, may get reflections and circular slips of their own, so that the light is brought into one, and made to shine. Some, too, write to show that she casts many of her beams upon earth in the line … under the inclined, subtended. To construct a diagram in illustration of this theory, and that, too, for many spectators, would be quite impracticable.

XVIII. "To sum up, I wonder how they manage about the half-moon's reaching us, together with the full round, and p. 222 the crescent. For if the mass of the moon, illuminated by the sun, were made of æther, or of fire, he would not have left her hemisphere shaded, and without lustre to the sense [perceptible], but had he touched her in ever so small a degree, in going round her, it would have been a natural consequence that the sun should fill her substance, and penetrate through the whole of it with his all-pervading light, from the want of any resistance. 1 For where wine touches water at the edge, or a drop of blood falls into any liquid, the whole quantity turns red, and changes to the colour of blood; in like manner, they pretend that the air itself is illuminated, not by emanations of any sort, or rays mingling themselves in it, but by a conversion and transformation due to impact and contagion: how do they imagine that star touches star, and light light, without mixing together or making any confusion or change at all, but to illume those objects only which they touch upon their surface? For the circle which the sun, as he goes round, traces and turns about with reference to the moon, at one time falls upon the line which divides the visible from the invisible portion of her body, at another time rises up vertically so as to cut them, and to be cut by the moon, producing various inclinations and relations of the lighted to the darkened part, the complete circle and the crescent forms in her appearance, all which proves more than anything else that her illumination is not the result of mixture but of contact, not ignition but irradiation. And since not only she is lighted up, but transmits hither the image of her light, she supplies yet further reason for our insisting upon our own explanation of her nature; for reflections are produced by no object that is porous or of loose texture. There is no such thing as light

p. 223 rebounding back out of light, or fire out of fire, easily conceivable; but the object that will produce opposition and fracture must necessarily be something ponderous and solid in order there may be impact against it, and resilience from it. At any rate the sun 1 himself penetrates the air because it neither furnishes obstacles, nor offers resistance; whereas from sticks and stones and clothes exposed to the light the sane sun gives back many reflections and irradiations. Thus, in fact, we see the entire earth illuminated by her, for she does not admit the light to a depth like water, nor through the whole substance like air, but whatever kind of orbit of the sun moves round the moon, and for as large a portion of her as is cut off thereby, just such another circle goes round the earth, and just so large a portion is there illuminating, and leaving the other not lighted up; for the hemisphere that is illuminated seems to be little larger in either case. Allow me to speak geometrically according to analogy, that if, there being three things which the light from the sun touches, namely, the earth, the moon, and the air, we see the moon illuminated, not in the same way as the air, but rather in the same way as the earth; it necessarily follows the two have the same nature, being made to be affected in the same way by the same agent." XIX. And when all had applauded Lucius, "Well done," I exclaimed, "you have added a good defence to a good subject; for I must not defraud you of your due." And he replied with a smile, "In the second place then, we must further make use of analogy in order that we may demonstrate the moon's affinity to Earth, not only from both being similarly acted upon by the sane thing, but by their both producing the sane effects. For that there is no one thing so similar to another amongst

p. 224 the phenomena connected with the sun, as the sun's being eclipsed is to his actual setting, 1 you must allow to me if you call to mind the eclipse which took place the year 2 before this meeting, when many stars became visible in different parts of the sky directly at the beginning of midday, and a mixture [of light and darkness] resembling daybreak pervaded the atmosphere, otherwise this Theon here will bring down upon us Mimnermus, and Cydias, and Archilochus, and Stesichorus, and Pindar to boot, all lamenting for 'the brightest one stolen away, and night coming on at midday, and the sun's ray [travelling] the path of darkness' … as they say. And above all, Homer, telling how 'men's countenances were covered over with night and darkness, and the sun was lost out of heaven and vanished around the moon,' … this happens when one lunar month is ending and the next commencing. The rest, with the accurate calculations of mathematicians, has been worked out and brought to a certainty; namely, that night is the shadow of the earth, and the eclipse of the sun is the shadow of the moon, when the light comes to be in it. For 3 the sun when setting, is blocked up by the earth against the sight; but when eclipsed he is blocked up by the moon, and both phenomena are occultations, but that of setting is due to the earth, that of eclipse to the moon, because she intercepts the view of him with her shadow. What takes place is easily understood from the following considerations. If the effect is the same, the agents are the same; for it is a matter of necessity that

p. 225 the same things should happen in the same case from the same causes. But that the darkness attending eclipses is not complete darkness, and does not condense the atmosphere in the same degree that night does, is a circumstance we ought not to be surprised at; for the substance is the same of the object that causes night and that causes the eclipse, but the magnitude of each is not equal: for the Egyptians, I think, say the moon is the seventy-second part of earth in size; Anaxagoras, that she is as big as the Peloponnesus. But Aristarchus proves that the moon's diameter bears a proportion [to that of earth] which is less than sixty to nineteen, but somewhat greater than one hundred and eight to forty. Consequently earth entirely takes away the sun from sight, by reason of her magnitude; for the obstruction she presents is extensive, and endures the space of a night, whereas the moon, even though she may occasionally hide the sun, the occultation has no time to last, and no extensiveness, but some light shows itself round his circumference that does not allow the darkness to become deep and unmixed. Aristotle (the ancient one, I mean 1) gives as one cause, besides some others, of the moon's being seen eclipsed more frequently than the sun, 'that the sun is eclipsed by the obstruction of the moon, whereas the moon is …' But Posidonius thus describes the phenomenon: 'The eclipse is the conjunction of the sun and the shadow of the moon, of which the eclipse … for to those people alone is the eclipse visible from whom the moon's shadow shall occupy and block out the sight of the sun.' And when he agrees that the shadow of the moon is projected as far as us, I do not know what more he has left himself to say, for of a star there can be no shadow, because that thing which is unillumined is designated shadow—now light does naturally not produce shadow, but destroy it."

p. 226 XX. "But after this," said he, 1 "what further evidence was adduced?" "The moon," I replied, "received the same explanation as to her eclipse." "You have done well to remind me," said he, "but beforehand, on the supposition that you are all convinced and hold that the moon is eclipsed because she is overtaken by the shadow, I now direct myself to the reason—or would you prefer that I should make a lecture and a display of eloquence beforehand, by enumerating the various attempts at the explanation, one after the other?" "Yes, truly, Theon," I replied, "lecture on these points; for I too require some persuasion, having only heard the question stated in this way—that the three bodies being come upon one straight line, namely, the earth, the sun, and the moon, the eclipses then happen, because the earth takes away the sun from the moon; on the contrary, the moon takes away the sun from the earth, for the sun is eclipsed when the moon, and the moon when the earth stands in the middle of the three; of which cases the one happens in the conjunction, 2 the other in the time of full-moon." 3 Then Lucius remarked: "These are about the most important of the theories current; but first of all, take in hand, if you please, the explanation derived from the figure of the shadow; for it is a cone, as though a great fire or light projected a mass, less indeed than a sphere, but still spherical in form, for which reason in eclipses of the moon the outlines of the darkened parts against the bright ones have their edges circular; for whatever sections a round thing coming in contact with another round thing, may either receive or produce, as they go off in all directions, they are made circular by reason of their resemblance [to what produced them]. In the second place, I fancy you know that the moon is first eclipsed on

p. 227 the parts towards the east; whereas the sun is on those towards the west, because the earth's shadow moves towards the west from the east. The sun and the moon, on the contrary, move towards the east. All this, visible facts enable us to discover, and may be understood without very lengthy explanations, and from them the shadow as the cause of the eclipse is established. For when the sun is eclipsed by being overtaken by, and the moon by meeting that which causes the eclipse, probably, or rather, necessarily, the sun 1 is first overtaken from behind, the moon from the front, for the occultation begins from that side where the object in front first casts the shadow, and the moon first casts it upon the sun from the west, as she is racing against him, but upon her he casts it from the east, because she is moving below in a contrary direction, from the east. Thirdly, then, consider the question of the duration, and of the extent of her eclipses. When she is eclipsed high in heaven and at her apogee she is obscured for only a short time, but being in her perigee and low when thus affected, she is greatly oppressed, and emerges with difficulty from the shadow. And yet, when she is low, she is making the greatest movements, but when high the smallest of all. But the cause of the difference lies in the shadow, for it is broadest at the base, as all cones are, and contracting gradually, at the top it ends in a sharp and fine point. Consequently, the moon entering into this shadow when she is low down, is caught by it in its largest circumference and passes through its deepest and darkest part, but when up high, just grazing the shadow, as though in shallow water, she quickly makes her escape. I shall pass over all that has been said with special reference to bases 2 and transits; because they admit the cause so far as possibility

p. 228 goes. But I return to the argument before me, that has ocular demonstration for its starting point. For we see that fire out of a shady place shows itself and shines abroad all the more; whether through the density of the obscured air not allowing of divergences and dispersions, but keeping together and compressing the element in one place; or else this is an affection of the sense [vision], just as hot things compared with cold seem hotter, and pleasures compared with pains seem more intense, even so bright things contrasted with dark become conspicuous, because they exaggerate their appearance through the opposite affections of the sense: the former supposition of the two is likely to be the more probable, for in the sunshine every sort of fire doth not only lose its brightness, but through yielding thereto becomes inoperative and duller; because the heat disperses and diffuses its proper force. If then the moon possesses an infantine and ineffective fire, being 'a feminine star,' as these philosophers pretend, it befits her to be affected in none of the ways in which she is affected at present, but altogether the contrary of them all; she ought to appear where now she is hidden, and be hidden exactly where she now appears: that is to say, be hidden for the rest of the time as being obscured by the circumambient æther, but emerge and become visible every six months, and again every five, when she enters into the shadow of the earth. For the 365 revolutions of the ecliptic full moons contain 404 periods of six months, and the rest of five months each. It would therefore be necessary that the moon should be visible at intervals of so many months, because she became conspicuous in the shadow; 1 but she … becomes eclipsed and loses her light, but recovers it again, when she emerges from the

p. 229 shadow, and often shows herself by day, as being anything rather than a fiery or star-like substance." XXI. Lucius having said this, Pharnaces and Apollonides in a way came into collision with each other [in their eagerness to answer him], but when Apollonides gave up the turn, Pharnaces continued, "This fact does most of all prove the moon to be a fire or a star, for she is not entirely invisible during eclipses, but displays the hot-coal 1 and grim colour which is her own proper hue." But Apollonides stood firm with respect to the shadow, "for [he said] the mathematicians always so denominated the unillumined place, and that the heavens did not admit of 'shadow.'" "This [said I] is rather the disputing captiously with a name than dealing philosophically and mathematically with the fact, for the place obstructed by the earth, if one chooses not to call it 'shadow,' but 'unillumined region,' it is all the same unavoidable that the moon, on coming into it … and altogether," added I, "it is silly to say the shadow of the earth does not reach so far.… the shadow of the moon impinging upon the sight, and … towards the earth, causes an eclipse of the sun. I will now turn to you, Pharnaces, for that coal-like and glowing 2 colour, which you pretend is the natural complexion of the moon, is really that of a body that possesses density and depth; for in things unsubstantial no remnant or vestige of flame is accustomed to remain; nor is there any food for fire except in a solid body that will receive and nourish the spark kindling it; as Homer also hath sung,

"'When the fire-flower was spent and quenched the blaze, Spreading the ashes wide.' [paragraph continues] For the 'charcoal' is probably not fire, but an ignited substance, and affected by fire dwelling upon, and wearing p. 230 itself out upon a mass which is both solid and possessed of durability; whereas the flames are but the lighting up and jets of an unsubstantial nutriment and material, speedily consumed by reason of its weakness. Consequently, nothing could have been so convincing a proof that the moon is an earthy and dense substance, than if 'smouldering coal' were proper to her as her colour. But is it not the case, my dear Pharnaces, that moons in eclipse assume various colours; and mathematicians (astrologers) define these colours, and distinguish them according to the time and the season? For instance, if the moon be eclipsed in the evening, she appears dreadfully black up to the third 1 and one-half hour, but if at midnight she emits this [just mentioned] purplish light, and fire, and flame-colour, whilst from the hour of morning 2 and half an hour later, the blush rises on her face; and finally at daybreak she puts on a dark blue and cheerful complexion, from which in reality the poets and Empedocles style her the 'Blue-eyed.' 3 When, therefore, we see the moon putting on so many different colours when in the shadow, they do not deal fairly in dwelling upon a single one of them, namely, the smouldering coal, which we really may say is the most uncongenial to her of them all; and is rather a mixture and remnant of the fire shining through the shadow round about her; but her natural colour [we define] to be dark-blue and earthy. For whereas here below shady places in the vicinity of lakes and rivers that catch the sun are similarly dyed and made brilliant in robes of purple, yea, even of scarlet, 4

p. 231 and give forth many various images of colour, through the reflections of the light, what wonder is it if the vast flood of shadow, falling as it were into a celestial ocean of light, not steady nor at rest, but agitated by stars infinite in number, and receiving mixtures and changes of all kinds, should extract different colours at different times, and give them out from the moon? A star, or a fire, would not in the shadow show itself black, or glaucous, or dark blue; but over mountains, or plains, or sea, many variations of colour from the sun go and come; and he casts the lustre of the dye, 1 tempered with shadows and with mists, as with the hues of the painter's palette; whereof that of the sea, widely diffused, Homer hath given a name to, calling it 'violet-coloured,' 2 and 'wine-faced ocean,' and elsewhere the 'purple wave;' and, again, 'blue-green sea,' and the 'white calm;' whereas the variations about earth of colours showing themselves differently at different times he has passed over in silence as being endless in quantity. The moon is not likely to possess only a single visible appearance like the sea; but much more so to resemble the earth in her nature, concerning which Socrates of old told a fable, whether that he was hinting at this, or describing, it may be, some other creation. 3 For it is neither incredible nor astonishing if she, having nothing in herself that is corrupting or turbid, but extracting the pure light out of heaven, and being full of heat, not of a consuming and fierce fire, but one that is liquid and harmless, and consistent with her nature, should possess wondrous beauties

p. 232 of scenery, flame-coloured hills, zones of purple, gold and silver, not dug out from her bowels, but cropping up in abundance to the surface, or overlaid upon polished eminences. 1 And if the sight (vision) of these things penetrates through the shadow differently at different times, as far as us, by reason of some difference and variation of the surrounding medium (atmosphere), the moon doth not thereby lose the preciousness nor the holiness of her glory, which … being held sacred by mankind, she is something more than 'a turbid and dreggy fire,' as the Stoics pretend. Fire, however, with the Medea and Assyrians enjoys honours well suited to barbarians, who worship things hurtful before things worthy of reverence, by way of deprecating their anger; but the name of Earth is, I ween, dear to all, and to the Greek even venerable, and with us 2 it is the hereditary rule to worship her in the same way as any other deity. We men are far from thinking the moon, which is a celestial earth, to be a body without life, and without mind, and destitute of those things which the gods have a right to enjoy, when we, by law, pay the requital for her blessings, and naturally respect that which is superior in virtue and in power, and therefore to be respected. Wherefore let us believe that we do not offend in supposing her an earth; and as for this her face visible to us, just as our own earth contains deep recesses [let us believe that] in the same way she too is opened out into vast gulfs, containing either water or darkened air, into which the sun's light doth not descend, or even touch, but falls short of them entirely, and produces a reflection that is dispersed and lost in those places."

XXII. Then Apollonides, scornfully interrupting, exclaimed: "What, then, in the Moon's own name, does it p. 233 seem to you possible that this appearance is nothing but shadows of streams or of deep ravines, and comes all the way from the moon to us here to our sight? Perhaps you do not consider the consequences, must I tell them? Listen, then, even though you be not ignorant of them already. The diameter of the moon measures twelve fingers’ breadth, 1 as it appears to the eye, at her mean distances; whilst of the black and shaded parts each one appears larger than a half digit, so as to be larger than the twenty-fourth part of the diameter; and, again, if we should estimate the circumference of the moon at thirty thousand stadia 2 only, and the diameter at ten thousand, according to the rule, then each one of the shaded parts in her, will not be less than five hundred stadia. 3 Consider, pray, in the first place, whether it be possible that such cavities and such great inequalities of surface should exist in the moon as to produce an obscuration of this extent. In the next place, being so large, why are they not perceptible 4 to us? "And I, smiling at him, replied, "Well done, Apollonides, to have invented such a demonstration, on the strength of which you will make out both yourself and me to be bigger than those Aloads 5 of old; not, however, at all times of day, but chiefly at sunrise and sunset; you think that because the sun makes our shadows enormous, the fact furnishes this fine argument to the sense, that if the shadow cast be big the thing casting the shadow must be exceeding great. In Lemnos neither of us, I well know, has ever been; both of us, however, have often heard that popular iambic line—

"'Athos has hid the flank of Lemnian Cow.' p. 234 [paragraph continues] For the shadow of the mountain, as it seems, strikes upon a little cow of bronze, extending a length of no less than seven hundred 1 stadia across the sea … 2 to be the height that casts the shadow; for the reason that the divergences of the light make the shadows many times greater than the bodies themselves. Come, pray, and consider that the sun is at his greatest distance from the moon at what time she is full, and produces the most distinct figure of the face by reason of the deepness of the shading; for it is the receding of the illumining light that makes the shade deep, not the greatness of the inequalities on the surface of the moon. And, again, neither do the rays of the sun allow the projecting parts of mountains to be discerned by day, whereas their deep places, valleys, and shaded parts are visible from a great distance; it therefore is nothing strange if it is not possible to discern distinctly the reception (of solar light) and the illumination of the moon, whilst the strong contrasts of the shaded against the bright parts do not escape our sight and observation. XXIII. "But the fact," continued I, "which seems still more to upset the alleged reflection of light from the moon, is that when people are standing in reflected lights, it comes to pass they see not only the thing illuminated but the thing that illuminates. For when a bright light cast from water is dancing up and down against a wall, the sight of it takes place in the point that is illuminated in consequence of the reflection; it (the sight) distinguishes three different things, namely, the reflected light, the water producing the reflection, and the Sun himself from whom the ray, falling upon the water, has been reflected. These points being confessed and evident, (the Stoics) recommend such as assert the earth to be illuminated by

p. 235 the moon, 1 to demonstrate that the Sun shows himself (is reflected) in the moon in the same manner 2 by night, when the reflection from him is produced. But as he does not appear then, they believe that the illumination takes place in some other way than by reflection: but if this be not so, then neither is the moon an earth." "What answer, then, must be made to them?" replied. Apollonides, "for the phenomena of reflection are in all probability universal, and like our own." "Certainly," said I, "in one way they are universal, but in another way they are not universal. In the first place, observe how these people take the phenomena of the spectrum, upside down and inside out: for upon earth and below it is the water, but above earth, and on high, it is the moon. 3 Consequently the reflected rays make the form of the angle corresponding—the one having its apex 4 above upon the moon, the other having it below upon the earth. Let them, therefore, not demand that it shall produce every image proper to mirrors, or an equal reflection from every distance—for in so doing they are fighting against demonstration. But those who make out the moon to be a body, neither polished nor fluid like water, but ponderous and earthy, I understand how they borrow from the sun what the appearance is in her that meets the sight: for neither does milk produce the same kind of mirrors, 5 nor render back reflections (as the water), owing to the inequality and density of its particles: by what means, therefore, is it possible that the moon should send out from herself an image in the same way as the more brilliant surfaces of mirrors? And yet, even in these, if a cobweb, or rust, 6 or roughness should cover the

p. 236 focus from which the image is generated it is [not] 1 reflected and imaged; and the mirrors themselves are seen, but give back no reflection. And whoso pretends that either our sight should reflect upon the sun, or else that the moon should not reflect the sun from herself upon us, is ridiculous 2 by his requiring the eye to be a sun, the sight the solar beam, and the moon the heavens. For that the Sun's reflection, impinging with a blow upon the moon by reason of its intensity and brightness, should be carried as far as us, is reasonable enough; whereas the sight being feeble, unsubstantial, and ever so small a fraction [of the solar light], what wonder is it if it neither produces an impressive stroke, nor in rebounding preserves its continuity, but is broken up and comes to an end; not possessing a large stock of light, so as not to be dissipated around the inequalities and roughnesses of the (moon's) surface? From mirrors, indeed, and other reflecting surfaces, it is not impossible for the proceeding reflection to strike upon the eye, as it is near to its origin; but from the moon, even though there should be some slippery glances of herself, they will be feeble and indistinct, and come prematurely to au end by reason of the length of the distance they have to travel. And, besides, concave mirrors make the reflected light more intense than that surrounding them, so as frequently to emit a flame; whilst the convex and spherical kinds, by reason of the light striking on them from all sides, produce a feeble and indistinct For you observe, 3 indeed, when two rainbows appear, from a cloud enveloping another cloud, that the one enclosing the other shows its hues weak and confused: because the exterior cloud, lying further off from