Chapter XV: Introduction (10)

[384] As this is the value given by Alfraganus, we must here understand Arabian miles. The distances from Rome to the north and south pole are therefore probably equal to 3500 to 9750 English miles, and both are a little too large, because the half circumference of Earth is too large. The proportion is about right, however, for Rome is nearly three times as far from the south pole as the north, her latitude being 42° N. Alfraganus placed her in the fifth climate, at the northern boundary of which he said the pole was elevated 43½°. ------------------------------------------------------------------------

Lastly, let us imagine a circle on the globe, which will be at equal distances everywhere from _Maria_ and _Lucia_ [the equator]. According to the opinions of the astrologers, if I understand them aright, and according to what is said by Albertus Magnus and by Lucan, this circle would divide the dry land from the ocean there in the south, approximately along the extremity of the First Climate, where amongst others live the Garamantes, who go almost always naked, to whom Cato went when fleeing from Cæsar.

“Approximately,” because the southern extremity of the First Climate, according to Alfraganus, lay a little north of the equator, although land extended, and was sparsely inhabited, as far the equator (see p. 186).

Dante speaks again of these extra-climatal races in _De Mon._ I. xiv. 43-51, where he contrasts the Scythians who live beyond the seventh climate, and therefore endure extreme inequality of days and nights, and suffer almost intolerable cold, with the Garamantes who live under the equator, where days and nights are always equal, and the heat is so intense that they can scarcely bear any clothing. Since “the astrologers who determine the climates”[385] had fixed their northern limit at 50½°, nearly the whole of Britain also lay, like barbarous Scythia, in this scarcely habitable region of long nights and bitter cold!

------------------------------------------------------------------------ [385] _Qu._ xix. 36. ------------------------------------------------------------------------

When we have marked these three places on the globe, _i.e._ the two poles and the equator, it is easy (Dante goes on) to see how the sun circles. I say then, that the heaven of the sun turns from west to east, not directly against the diurnal movement—that is, the movement which produces day and night—but obliquely against it, and so that its middle circle, which is similarly between its two poles, and on which is the body of the sun [_i.e._ the ecliptic], cuts in two opposite points the circle of the two first poles [the equator], that is, at the beginning of Aries and the beginning of Libra; it diverges from that circle in two arcs, one north and the other south. The highest points of these arcs are equally distant from the first circle in either direction, being 23 degrees and a little more; and the one summit is at the beginning of Cancer, and the other at the beginning of Capricorn.

Therefore, when the sun is in the beginning of Aries, travelling in the mid-circle of the first poles [the equator], _Maria_ will see this sun circling the world, low down on the ground, or on the sea, like a mill-stone only half of which is seen, and day after day he will be seen to rise, like the screw of a press, until he has performed about ninety revolutions, or a little more. When these revolutions are accomplished, he will be as high in the sky above _Maria_ as he stands in the sky of the Garamantes at middle-tierce at the time of equal days and nights.[386]

------------------------------------------------------------------------ [386] Adopting the reading of Dr. Moore: “nella mezza terra, alla mezza terza,” that is, “at the equator at middle-tierce.” See _Studies in Dante_ III. 107, 108. ------------------------------------------------------------------------

[From _Conv._ IV. xxiii. and III. vi., where Dante explains the use of temporal hours, we learn that mid-tierce on the day of the equinox is an hour and a half after sunrise, or 7.30 A.M. Since the sun moves through 360 degrees divided by 24, that is 15 degrees, in an hour, and his motion is vertical in equatorial countries at the equinox, it would bring him in 1½ hours to 22½ degrees above the horizon. His greatest height above the horizon at the pole is only one degree more than this, for it is obviously equal to the greatest distance between the equator and the ecliptic, _i.e._ 23½ degrees, since at the pole the equator coincides with the horizon. This gives a good idea, therefore, of the appearance of the sun in the sky to the people at _Maria_, and is a striking illustration of the difference between the polar sun and the equatorial. For at the time mentioned, the sun has only a quarter the height which it will attain at noon, when it will pass through the zenith of the Garamantes; yet this is the highest position in which the inhabitants of _Maria_ can ever see it].

If a man stood upright in _Maria_, and kept turning his face to the sun, he would see it move to his right [as we do].

After reaching his greatest height in the sky, the sun would begin to descend again, in the same spiral way like a screw turning, for another ninety revolutions or so, until once more he was circling down on the horizon, only half his body visible.

Then he would be lost to sight altogether, and would begin to be seen in _Lucia_, where he would rise and descend in just the same way as in _Maria_. But if a man faced the sun in _Lucia_, he would see it moving to his left [as one does in Australia where it goes north at noon].

(Maria, Lucia, imaginary cities at the North and South poles).]

We see, then, that these places have one day in the year which is six months long, and one night of equal length, and when it is day with one, it is night with the other.

Now on the circle on the globe where the Garamantes live [the equator], the sun when in Aries goes exactly overhead, not circling horizontally like a mill-stone, but vertically like a wheel, and exactly half of this wheel is visible above the horizon.

After this, the sun is seen to depart and go towards _Maria_ for about 91 days; then in about the same time it returns, and enters Libra; then it goes towards _Lucia_ for about 91 days, and in the same period returns. And this place, which circles the entire globe, always has equal day and night, on whichever side of it the sun is; and twice in the year it has a very hot summer, and twice a mild winter.

The regions which are between the two imaginary cities and the mid-circle, see the sun in different ways, according to their distance from these places, but the details, our author says, he will leave to the ingenious reader,

“Siccome omai, per quello che detto è, puote vedere
chi ha nobile ingegno, al quale è bello un poco di
fatica lasciare.”[387]

------------------------------------------------------------------------ [387] “For now, after what has already been said, the rest may be understood by whomsoever has a noble mind, to which it is well to leave a little labour.” (_Cf. Par._ x. 22-25). ------------------------------------------------------------------------

He draws attention to the interesting fact, which follows from the above, that in the course of a year (when the heaven of the sun has made a complete revolution and returned to the same place), every part of this globe on which we live has received an equal amount of daylight. And the essay ends in an apostrophe which recalls the reproof of Virgil to those who will not look up to the skies:[388]

“O ineffabile Sapienza che a così ordinasti, quanto
è povera la nostra mente a Te comprendere! E voi,
a cui utilità e diletto io scrivo, in quanta
cecità vivete, non levando gli occhi suso a queste
cose, tenendoli fissi nel fango della vostra
stoltezza.”[389]

------------------------------------------------------------------------ [388] _Purg._ xiv. 148-151.

[389] “O unspeakable Wisdom who hast thus ordained, how poor is our intellect to understand Thee! And you, for whose benefit and pleasure I am writing, in what blindness you live, not lifting up your eyes to these things, but keeping them fixed on the slough of your folly.” ------------------------------------------------------------------------

It is interesting to compare this passage with the parallel passages in Alfraganus and Ristoro. The astronomer is concise and clear; the monk is diffuse and apt to repeat himself; the poet is quaintly picturesque. Both the Italians evidently draw the main facts from the Arab, and all use the illustration of a mill-stone to explain the horizontal motion of the heavens at the pole: here are the three corresponding passages:—

“Coelumque molæ trusatilis instar gyrum
vertitur.”[390]

“Lì si volgera il cielo attorno con tutte le sue
stelle, in modo di macina.”[391]

“Conviene che _Maria_ veggia ... esso sole ‘girare
il mondo’ ... come una mola.”[392]

------------------------------------------------------------------------ [390] “And the sky revolves like a mill-stone.” _El. Ast._ ch. vii.

[391] “There the sky will revolve, with all its stars, mill-stone
fashion.” _Comp. del Mondo._ I. xxiii.

[392] “It follows that _Maria_ must see this sun ‘circling the world’ like a mill.” _Conv._ III. v. 142-147. ------------------------------------------------------------------------

Dante alone uses the figure of a wheel to illustrate the vertical motion at the equator; he perhaps takes from Ristoro the idea of the spiral. For the latter describes the path of the sun as a “via tortuosa, la quale i savi chiamano spira;”[393] but he explains it as like a string wound round a stick, Dante like the screw of a press. Dante is dealing only with the sun, and does not enter into details about the visibility of the zodiacal signs like the other two authors; but on the other hand he goes south to the other pole, which apparently does not interest the others, perhaps because the southern hemisphere was thought to be uninhabited. But the poet has added life to his description by supposing both poles inhabited, placing there his imaginary, mysteriously-named cities of “Maria” and “Lucia.” On the equator, where Ristoro has the mythical city of Arym, whose wise and prosperous citizens enjoy a perfect climate, Dante, relying more on the classics, lets his barbarous Garamantes run about naked most of the year, under the fierce equatorial sun.

Needless to say, his little homily in conclusion is all his own; it is more interesting to find that he alone mentions the opposite movements of the Sun, to right and left respectively in the north and south hemispheres,[394] and the fact that every part of the earth receives the same amount of sunlight in a year. This may have been suggested by someone else, but one would like to think he arrived at it independently, when thinking over the facts.

------------------------------------------------------------------------ [393] “A winding path, which the learned call a spiral.”

[394] “Lucan, who was well known to Dante, had observed that shadows cast by the sun in the southern hemisphere travel to the right instead of to the left, and fall southwards when with us they fall to the north.” Moore, _Studies in Dante_ i. p. 239. ------------------------------------------------------------------------

In the light of this treatise, which describes so truthfully the path of the sun, and its effect on the seasons in different latitudes, we may explain two rather puzzling passages in the _Divine Comedy_.

One is at the beginning of the tenth canto of the _Paradiso_, where Dante wishes his readers to realize the position of the sun when he entered it with Beatrice, and the great importance of this position. “Lift your eyes with me, reader,” he says, “to that place in the lofty heavens where the one motion meets the other, and see how the oblique circle which carries the planets branches off from that point.” The reader is now familiar with the “two chief motions,” and knows that one is the diurnal, from east to west, the other the planetary periodical motions in the opposite direction; they meet at the equinoxes, where the ecliptic cuts the equator. It is the spring equinox which Dante is speaking of, for a little further on he says that the sun, situated in the place above-mentioned, was circling in those spirals which bring him to us earlier every day (lines 31-33). Now if the path of the planets were not thus oblique, he continues, much virtue in heaven would be lost, and almost every earthly power dead. Even if the obliquity were merely less or more, the universal order of both heaven and earth would suffer greatly. But why this should be so he leaves his readers to think out for themselves, having a greater matter in hand which demands all his attention.

It is easy to see that if the sun always moved in the equator, without departing from it either north or south, he would rise every day to the same height in the sky, and there would be no change of seasons anywhere on the earth; he would always be overhead at noon to Dante’s Garamantes, living on the equator, and always just on the horizon, day and night, to the people of “Maria” and “Lucia” at the Poles. If the ecliptic made a greater angle with the equator the seasons would be more marked, and the sun would rise higher in summer in high latitudes. If the angle were less, the reverse would be the case. Moreover if sun and moon and all the planets followed the same track, they would be constantly eclipsing one another.

But if we would understand the full meaning of—

“Se la strada lor non fosse torta,
Mota virtù nel ciel sarebbe in vano,
E quasi ogni potenza quaggiù morta.”[395]

------------------------------------------------------------------------
[395]
“If their pathway were not thus inflected,
Much virtue in the heavens would be in vain,
And almost every power below here dead.”
_Par._ x. 16-18. (_Longfellow_).
------------------------------------------------------------------------

we must turn to thirteenth-century Ristoro of Arezzo, who has set forth in detail the results which he believed would follow from a change in the ecliptic. If all the seven planets moved in the same narrow path, there would be much less variety in their “aspects,” and therefore in their influences upon the earth; and in the frequent eclipses one would prevent the other from looking at the earth (“impedimenterebbe l’uno l’altro a guardare la terra”), and so hinder its action. And since it is the northward movement of the sun which causes our plants to blossom, and later to bear fruit, if there were no such motion we should see no renewal of life. He argues further that if the obliquity of the ecliptic were greater, countries in high latitudes would have too severe a winter to be inhabited; while if it were less, the summer there would not be warm enough for the ripening of harvests; therefore in whichever way it differed from the actual value, a smaller part of the earth would be habitable.

“Or ti riman, lettor, sopra il tuo banco,
Dietro pensando a ciò!”[396]

------------------------------------------------------------------------ [396] “And now remain, reader, on your bench, thinking over this!” _Par._ x. 22, 23. ------------------------------------------------------------------------

How much of this was in Dante’s mind it is hardly possible to say, but it is evident that the “via tortuosa” of the seven planets, and its effects on the earth, was a favourite subject for thought in his time.[397]

------------------------------------------------------------------------ [397] Thus Petrarch: “Le stelle vaghe e lor viaggio torto.” (“The wandering stars and their winding way.”) _Sonetto de Morte di Madonna Laura._ ------------------------------------------------------------------------

But the most famous passage relating to the sun’s path and its aspect in strange latitudes is _Purg._ iv. 52-84.

Here Dante is able at once to understand the startling appearance of the sun travelling to his left instead of his right, as seen on the first morning in Purgatory, for he grasps the full meaning of Virgil’s explanation, and caps it, in a way which seems astonishingly quick-witted to unastronomical readers!

The two poets had begun to climb the mountain just at sunrise, and sat down to rest on a ledge at about half-past nine, looking east. Dante at first looked down at the shore, whence he had so painfully climbed, then raised his eyes to the sun, and was amazed to find that its rays struck him on the left shoulder.

Virgil, seeing his astonishment, explains why the sun is going north instead of south as it climbs the sky. The sun is now in Aries, and therefore on the equator, as we know from several passages, but Virgil begins by saying that if it were in Gemini [a more northerly sign] and kept to its ancient path, Dante would see it travelling still further northwards in its daily course. “If Castor and Pollux [stars in Gemini] were in company with that Mirror [the sun] which carries his light up and down [_i.e._ goes north and south alternately], you would see the glowing zodiac [that part in which the sun is] revolving still closer to the Bears.” Gemini is literally nearer to the constellations of the Bears than Aries, but this is not the sense of Virgil’s statement: he means merely to indicate the north in general (see Ptolemy, p. 157). “To understand why the sun goes north,” Virgil says, “you must know that this mountain and Zion [Jerusalem] are so situated on the earth that one is precisely antipodal to the other; and so, the sun’s path being between them, when he is viewed in one direction from Jerusalem, he is viewed in the opposite direction from Purgatory. If you turn from the east to your right to see him from Jerusalem, you must turn to your left in Purgatory.” Virgil speaks of the sun’s path or the ecliptic as the path which Phaëton was not able to keep, and he describes the two antipodal places as having one and the same horizon but two entirely different hemispheres.

“Certainly,” replies Dante, “I have never seen anything so clearly as I now perceive what at first puzzled me. For the middle circle of the celestial motion,[398] which is called the equator in a certain art [astronomy], and which always remains between the sun and winter, [the sun crosses it departing from us in either hemisphere at the autumnal equinox], here lies to the north of us, for the reason you have given [namely, that we are in the southern hemisphere], whilst the Hebrews [inhabitants of Jerusalem] see it towards the hot region [the south].”

Observe that the expression used of the equator “che sempre riman tra il sole e il verno,”[399] distinctly suggests the reversed seasons in the southern and northern hemispheres, so that Dante has no intention, as Dr. Moore suggests, of assuming by a poetic licence that it is spring in Purgatory as well as in Italy.[400] It is autumn in the southern hemisphere, but this need not distress us: the holy Mountain knows no inclement weather,[401] and in the Garden of Eden on its summit spring flowers and autumn fruits eternally flourish together.[402]

An allusion is made to a tropical summer in “la terra che perde ombra.”[403] Tropical Africa is intended, where the sun at certain times passes directly overhead, and therefore casts no shadows, as the Alexandrian astronomers had observed (see p. 117).

------------------------------------------------------------------------ [398] _Cf. Conv._ III. v. 76, 191.

[399]
“Which always remains between the sun and the winter.”
_Purg._ iv. 81.

[400] _Studies in Dante_ iii. p. 166.

[401] _Purg._ xxi. 46-48; _Purg._ xix. 38.

[402] _Purg._ xxviii. 143.

[403] “The land where shadows are lost.” _Purg._ xxx. 89. ------------------------------------------------------------------------

Did Dante believe that no land exists anywhere in the southern hemisphere? There are some indications that he thought it possible to push the limits of the habitable earth a little beyond the equatorial boundary of Alfraganus. There would be no heresy in lengthening the southward extremities of Africa or Asia, because all that the Church forbade was to plant another land in the south, separated from us by a vast ocean or impassable torrid zone, and to people it with inhabitants, who could not therefore be descendants of Adam or have the Gospel preached to them. Nor would there be any inconsistency with the poet’s own description of our hemisphere as that covered by “la gran secca,”[404] or with the voyage of Ulysses, on which he saw no land but the Mountain of Purgatory; for he sailed south-west, not due south, and the “mondo senza gente”[405] was “diretro al Sol.”[406]

------------------------------------------------------------------------ [404] “The great dry land.” _Inf._ xxxiv. 113.

[405] “The unpeopled world.” _Inf._ xxvi. 117.

[406] “Behind the sun.” _Ibid._ ------------------------------------------------------------------------

The indications are as follows:—

(1) The passage quoted above, where it is said that the equator “divides the uncovered land from the ocean”[407] is ambiguous in the original, and might mean “divides the land uncovered by Ocean.”

------------------------------------------------------------------------ [407] _Conv._ III. v. 117, 118. ------------------------------------------------------------------------

(2) Shortly before, he has distinctly admitted that there is some land in the southern hemisphere, by saying that the north celestial pole is visible to _nearly all_ the land not covered by sea, and the south is hidden from _nearly all_ of it. The first is true in any case, since though the pole is theoretically visible as far as the equator, it is often hidden by mist or rising land on the northern horizon; but unless the second “nearly” has been added by a (somewhat natural) mistake of a copyist, it can only apply to lands in the southern hemisphere.[408]

------------------------------------------------------------------------ [408] Refraction makes the pole visible a little before one reaches the equator, but such refinements need not be considered in dealing with a popular work like the _Convivio_. ------------------------------------------------------------------------

(3) There is a stanza in _Canzone XV._ which suggests that Dante believed Ethiopia to be on the south side of the equator. Classical and mediæval cosmographers had very vague ideas about the extent and position of this country. Dante describes a wind raised in its deserts by the sun, which _now_ is heating it (implying the time of summer?); but the same wind, crossing the sea to Europe, darkens all _this_ hemisphere, bringing clouds which fall in snow.

“Levasi della rena d’Etiopia
Un vento pellegrin, che l’ aer turba,
Per la spera del sol, ch’ or la riscalda,
E passa il mare, onde n’adduce copia
Di nebbia tal, che s’ altro non la sturba
Questo emisperio chiude tutto, e salda;
E poi si solve, e cade in bianca falda
Di fredda neve, ed in noiosa pioggia.”[409]

------------------------------------------------------------------------
[409]
“There riseth up from Ethiopia’s sands
A wind from far-off clime which rends the air,
Through the sun’s orb that heats it with its ray.
The sea it crosses; thence, o’er all the lands
Such clouds it brings that but for wind more fair
O’er all our hemisphere ’twould hold its sway;
And then it breaks and falls in whitest spray
Of frozen snow and pestilential showers.”
_Canz._ xv. 14-21. (_Plumptre_).
------------------------------------------------------------------------

However, it may be said that “or la riscalda”[410] means merely that it is always hot in the tropics, even when we have winter, and that “questo emisperio”[411] cannot possibly mean the whole of the terrestrial northern hemisphere from equator to pole, but simply describes the appearance of the hemispherical sky,[412] completely covered with cloud.

These doubtful passages are not strong enough to set against the explicit statement in the _Quæstio_ that the habitable earth extends from the equator to the Arctic circle and no further.[413] Letters and reports from missionaries and traders, none of them scientific, did not shake Dante’s faith in the limits laid down by Ptolemy and Alfraganus. His geography was utterly wrong, but his astronomy was right; and therefore, although he had no idea of what he would see on our globe in untravelled latitudes, he knew exactly, and has described vividly, what he would see in the sunny sky.

------------------------------------------------------------------------ [410] “Now heats it.”

[411] “This hemisphere.”

[412] Just as in _Par._ xxviii. 80.

[413] _Qu._ xix. 53-57, and repeated in xxi. 36-40. ------------------------------------------------------------------------

9. CELESTIAL PHENOMENA AND TIME.

The foregoing quotations have shown how well Dante understood the changing appearances of the celestial phenomena as viewed from different latitudes: it now remains to be seen what were his conceptions of longitude.

A difference in longitude between two places makes no difference in the stars, nor in the apparent paths of the heavenly bodies, but they come to the meridian sooner in the more easterly place; and as it is the meridian passage of the sun which determines local time, this will vary in exact proportion to the distance east. When it is early morning in England, it is noon in Burmah, and evening in Fiji. As Alfraganus had observed (following Ptolemy), a celestial phenomenon such as a lunar eclipse, which is caused by an actual darkening of the moon’s surface when immersed in Earth’s shadow, is visible in every place where the moon is above the horizon, though the local hour differs.

It is otherwise with a total solar eclipse, for this is only visible from the very small portion of Earth on which the moon’s shadow falls as she passes between us and the sun (see fig. 44); and as this shadow moves on, owing to her own motion and the diurnal revolution combined, the eclipse becomes visible successively from different parts of the earth. Dante realized this when he quoted the argument of some theologians that the miraculous three hours’ darkness described in the Gospels could not have been caused by an eclipse of the sun, as Aquinas and others had suggested, because it was visible all over the earth at the same absolute time, that is, during the Crucifixion.[414] Some said, he tells us, that the moon went back and placed herself between us and the sun (for the moon at Passover time was always full, and therefore opposite the sun), so that the sun’s light should not come down (to us on the earth); others, that the sun hid itself, for a corresponding eclipse was seen by Spaniards and Indians as well as Jews.[415] Spaniards and Indians were supposed to live at the extreme western and eastern limits of the habitable earth: they were 180° in longitude, or 12 hours in time, apart, and Jerusalem was midway between them. Therefore the sun would be visible to all, though only just rising in India and just setting in Spain;[416] but it could not have been an eclipse that darkened it to all at the same time.

------------------------------------------------------------------------ [414] _Luke_ xxiii. 44.

[415] _Par._ xxix. 97-102.

[416] Dante believed the death of Christ to have taken place when it was noon in Jerusalem. _Conv._ IV. xxiii. 105-106. ------------------------------------------------------------------------

This passage shows that Dante was entirely orthodox and conservative in his geography, as far as longitude was concerned, and confirms us in the conclusion that he was so also with regard to latitude, and was not likely to accept contemporary evidence about lands south of the equator, or stars unknown to Ptolemy. In the _Divine Comedy_ there are several passages which refer to the same system, as for instance where Night is described as covering the whole region from “the Shore” to Morocco,[417] or where the time is stated to be noon on the Ganges, sunrise at Jerusalem, and midnight in Spain.[418] And in the _Quæstio de Aqua et Terra_ the system is thus clearly explained:—

“As all these agree in believing [the naturalists,
the astrologers, and the cosmographers], this
habitable earth extends in longitude from Gades,
which lies on the western boundaries of Hercules,
as far as the mouths of the Ganges, as Orosius
writes.[419] That longitude is such that at the
equinox the sun is setting upon those who are at
one of these boundaries, while it is rising upon
those who are at the other, as astrologers have
discovered by eclipses of the moon. Therefore the
aforesaid boundaries must be 180 degrees distant in
longitude, which is half the distance of the whole
circumference.”[420]

------------------------------------------------------------------------ [417] _Purg._ iv. 137-139.

[418] _Purg._ xxvii. 1-5.

[419] Orosius says: “Europæ in Hispania occidentalis oceanus termino est, maxime ubi apud Gades insulas Herculis columnæ visuntur.... Asia ad mediam frontem orientis habet in oceano Eoo ostia fluminis Gangis.”

[420] _Qu._ xix. 38-52. ------------------------------------------------------------------------

Gades is not the city of Cadiz, but two islands (the “Gades Insulæ” of Orosius), on which Hercules was said to have set up his Pillars, as a sign that no one should venture further; and they were thought to lie in the mouth of what we call the Straits of Gibraltar:[421]—

------------------------------------------------------------------------ [421] Moore, _Studies in Dante_ iii. p. 124. ------------------------------------------------------------------------

“quella foce stretta,
Ov’ Ercule segnò li suoi riguardi,
Acciochè l’uom più oltre non si metta.”[422]

------------------------------------------------------------------------
[422]
“The strait pass, where Hercules ordained
The boundaries not to be o’erstepped by man.”
_Inf._ xxvi. 107-109. (_Carey_).
------------------------------------------------------------------------

Through these Ulysses sailed, never to return.[423]

------------------------------------------------------------------------ [423] _Inf._ xxvi. 106-142. ------------------------------------------------------------------------

It is difficult to believe that a lunar eclipse had ever been observed simultaneously, and the local time compared, on the Ganges and at Gibraltar, as the above quotation from the _Quæstio_ declares: and if it had been, the astrologers, the cosmographers, and the naturalists would have found out that they were greatly mistaken, for the distance is little more than half what they thought. All that Ptolemy had said was that this was the right method for calculating longitudes, and he gave as an example an eclipse which had been seen at Arbela at the fifth hour and at Carthage at the second hour.[424] It was, in fact, an excellent method, and the only one before the day of chronographs and telegraphs; and it seems to have been assumed that Ptolemy’s guess of 180° for the extent in longitude of the inhabited earth was based upon it.

------------------------------------------------------------------------ [424] _Ptolemy’s Geography_, Bk. I. ------------------------------------------------------------------------

Then this 180° was considered, in the Middle Ages, as divided into two equal parts, the western half containing Europe and Africa, the eastern containing Asia. On the western front of Asia lay Jerusalem, thus holding the central position in the inhabited earth which was thought to be her right, on the authority of certain Scripture texts, as we saw.[425] This gave the Mediterranean a length of 90°, which of course is vastly too great. Even Ptolemy had only estimated it at 62°, and the Alfonsine Tables made it 52°, while the true distance is only about 42°.

------------------------------------------------------------------------ [425] See p. 176. ------------------------------------------------------------------------

Latitude, however, was much more easily measured than longitude, for it was only necessary to take the height of the pole star above the horizon with an astrolabe; and the latitude of Jerusalem is really just about midway between the supposed limits of the habitable earth, the equator and arctic circle, for it is nearly 32° north.

Some daring spirits ventured to suggest that the dry land stretched much further round the globe than was commonly supposed, so that one might sail from Spain to Asia in quite a short time, and they sheltered themselves behind the great names of Aristotle, Seneca, Pliny, and Esdras.[426] Albertus Magnus quotes Aristotle to this effect, although in another part of the same book (his _De Cælo et Mundo_), he repeats the usual phrase about the habitable Earth being all contained within one of the northern quadrants of earth. Roger Bacon expresses himself more boldly, and it is possible that he was impressed by the long journey of the Franciscan friar Rubruquis, on his mission to Central Asia, from St. Louis of France to the Emperor of the Mongols. Besides relating the story of this journey, Bacon speaks of men who were known to live in tropical Taprobane (Ceylon), and if there, why not also south of Capricorn? There may be delightful countries there, since it is the better and nobler part of the world, as Aristotle and Averroës taught.

Moreover, Dante’s own countryman, the learned Pietro d’Abano, maintained that there are habitable lands on, and even beyond the equator, and did not hesitate to quote conversations with Marco Polo as evidence, although this “most extensive traveller and most diligent enquirer” was accounted a romancer by most of his contemporaries. Had not Messer Marco told him that in islands south of the equator he had seen not only great rams with coarse stiff wool like the bristles of pigs, but human beings?[427]

------------------------------------------------------------------------ [426] _Esdras_ II. vi. 42.

[427] Beazley, _Dawn of Geography_ iii. 28, 29. ------------------------------------------------------------------------

Roger Bacon was banished from Oxford on a charge of heresy and witchcraft: Pietro d’Abano escaped the Inquisition by dying, in 1316. Men such as these belonged to the new age that was coming, the age that would throw away the old lesson-books, and begin to discover for itself—and they suffered in consequence. Dante belonged heart and soul to his own era, and clung passionately to its ideals and traditions. For him the Ganges still flowed into the all-surrounding ocean on the east coast of Asia, 90 degrees from Jerusalem, as Orosius had pictured it, and there is not the faintest echo in his writings of the voyages of his countrymen, Corvino and his bishops, or Polo and his companions,[428] between “Greater India” and “Zayton” (Amoy harbour), although they surely must have recognized, when they praised the great rivers of China, that these flowed into a sea many days’ journey beyond that into which the Ganges rolled its waters. Nor is there, on the other hand, any hint of the monstrous races with which Dark-Age superstition had peopled the remote regions of the earth, although they were regularly represented on the maps of that time. It is true that the “portolani,” or handy charts, of which the earliest known date from Dante’s life-time, showed none of these things, but depicted the coast-lands of the Mediterranean and Black Seas with marvellous accuracy: but they were only for pilots and merchant captains, and had nothing to do with scholars. The maps Dante would see were hung on church or monastery walls, or illustrated learned books; and the mappe-monde of Cardinal Heinrich of Mainz may be taken as typical of them all. It much resembles our great Hereford Map of the World, and was probably copied from the same original design.

------------------------------------------------------------------------ [428] Corvino and Marco Polo made the voyage in the same year, 1292, but in reverse directions. ------------------------------------------------------------------------

It is two hundred years older than Dante, but so stationary was geography throughout the Middle Ages that it might have been executed in his day, or, except for a few details, several centuries earlier.

Mediæval maps are as fascinating as a fairy tale, which indeed they much resemble. The shape is conventional, and not supposed to represent the true shape of the habitable earth; it is sometimes circular, sometimes quadrilateral, occasionally oval, as in the present instance. The east is here, as usual, at the top, and there we see the Paradise of Adam and Eve, and close beside it, to the north, the River Ganges, flowing into the great ocean which surrounds all the land. At the opposite or western extremity are the Pillars of Hercules, which two angels appear to be guarding. In the centre, but not so exactly or conspicuously central as in some other maps, we find “Hierusalem.” Along the south is the long narrow continent of Africa, with the Atlas and Ethiopian mountains; and the Nile, rising far in the south-west, after mysterious submergences and reappearances, finally flows into the Mediterranean, past the pictured Pyramids, here strangely called (according to Dark-Age myth) the Barns of Joseph. In the north another Angel points to the country where dwell the Gog-Magogs, and not far off are the lands of the Hyperboreans, here described as untroubled by disease or discord, of the “most wicked” Gryphons, and of the Dog-headed folk, adjoining the Arctic Ocean.

Italy is a very large country, roughly triangular, and in the Mediterranean to the south lie Sicily, the whirlpool Charybdis, the rock Scylla, Sardinia, Corsica, and other islands. Rome is figured as a battlemented city, about halfway between Jerusalem and the Pillars of Hercules.

_To face p. 344._

_Reproduced by permission from Beazley’s “Dawn of Modern Geography.”_]

This is where Dante also places the imperial city, for in his system it is about 45°, or 3 hours, east of Gades and west of Jerusalem. He tells us in one place that it was vespers in Naples when the sun rose in Purgatory,[429] and in another that when it was vespers or three o’clock in the afternoon in Purgatory, it was midnight “here”[430] which may mean Florence or Italy in general; both these statements indicate a difference of nine hours or 135° between Italy and Purgatory. Purgatory in the _Divine Comedy_ is exactly antipodal to Jerusalem, and therefore twelve hours distant in time;[431] and for the sake of his allegory Dante has so far departed from tradition as to place the Earthly Paradise here also.[432] These five places may therefore be diagramatically represented thus:—

------------------------------------------------------------------------ [429] _Purg._ iii. 25.

[430] _Purg._ xv. 1-6.

[431] _Purg._ iv. 68-71; xxvii. 1-5.

[432] _Purg._ xxviii. 142. Opinions differed as to its exact site, and some placed it in the ocean beyond the eastern limit of the habitable earth. In _V. E._ I. viii. 6-10, Dante says that the root of the human race was planted in eastern lands, but this refers to Adam’s home after the expulsion from Paradise. ------------------------------------------------------------------------

+---------------------------------------------------------+
EARLY <---------------- TIME ----------------------> LATE
12 hours 6hrs. 3hrs. 6hrs. 12 hours
---+----------+-------+----+---------+-----------+--------

Purgatory Gades Italy Jerusalem Ganes Purgatory

---+----------+-------+----+---------+-----------+--------
180° 90° 45° 0° 90° 180°
WEST <--------------- LONGITUDE --------------------> EAST
+---------------------------------------------------------+

With this key, Dante’s fondness for describing the time at one place by mentioning one of the others need be no stumbling-block, as it is to many readers.

The fact is that though Dante had none of our opportunities for changing time-reckoning by long journeys, nor for communicating with friends at the other side of the world, who wake while we sleep, the marvellous daily revolution of the skies had a fascination for him, and he delighted to picture a glorious sunrise taking place in one country while in another it was high noon, or the middle of the night. Thus, the beautiful description of the stars fading in the growing light of dawn, which we quoted above, is preceded by a picture of the sun glowing on the meridian some 6000 miles away (rather more than a quarter the circumference of the globe), while with us Earth’s shadow has sunk almost to a level plane.[433]

Again, Folco of Marseilles, when describing his birthplace, says that the greatest of all the seas (the Mediterranean) except the ocean which encircles all the habitable earth, stretches so far against the sun (i.e. from west to east), that the line of sky which is on its horizon at one end is on its meridian at the other.[434] If the sun were seen just rising on the eastern horizon at Gades, it would be on the meridian at Jerusalem and the time would there be noon.

------------------------------------------------------------------------ [433] _Par._ xxx. 1-3.

[434] _Par._ ix. 82-87. ------------------------------------------------------------------------

Dante’s hours are always reckoned from sunrise, and they are the “temporary” or Church hours. He defines both kinds in the _Convivio_. The same lines of his Ode which provided him with a text whereon to discourse of the sun’s movements, give him occasion to treat of the division of each day into hours, thus:—

“I say that the sun, in circling round the world,
_ne’er beholdeth aught so noble as this lady_, from
which it follows that she is, as the words affirm,
the most noble of all the things on which the sun
shines. And I say _in that hour_, etc. Wherefore
we must know that the _hour_ is understood in
two senses by astrologers. One sense is employed
when they assign twenty-four hours to the day and
night, that is, twelve to the day and twelve to the
night, however long or short the day may be. And
these hours become short or long in the day and in
the night, according as the day and night wax and
wane. And the Church uses hours in this sense when
she speaks of Prime, Tierce, Sext, and None; and
these are called temporal hours. The other sense is
employed when, of the twenty-four hours alloted to
the day and night, the day has sometimes fifteen
and the night nine, and sometimes the night has
sixteen and the day eight assigned to it, according
as the day and the night wax and wane; and these
are called equal hours. And at the equinox these
latter are always one and the same with those which
are called temporal; for it must needs be so when
the day and the night are of the same length.”[435]

The choice of these two examples of unequal days and nights seems to be another instance of Dante’s dependence upon Alfraganus, for in Chapter VIII. of the _Elementa Astronomica_ we read that the middle of the seventh climate (in which the inequality is greatest) has a longest day of 16 hours, and the middle of the fifth, of 15 hours; and in chapter IX. we find that Magna Roma is situated in the fifth climate.

In the fourth treatise of the _Convivio_, Dante returns to the same subject, and enters into further detail about Church hours and divisions of the day.[436] Our lives, like the arch of heaven which is always above us, consist of a rise and a decline, with a culminating point, and this point he fixes as normally reached at a man’s 35th year, as Ristoro had also done.[437] In the same way the day rises and declines, and culminates at the sixth hour; and it is the most noble hour of the day and the most virtuous (in the old Latin sense of virtue as strength, efficacy).

------------------------------------------------------------------------ [435] _Conv._ III. vi. 7-32.

[436] _Conv._ IV. xxiii. 50 to end.

[437] _Comp. del Mondo_, I. xxii.
“La sesta ora, cioè il mezzo del dì, è la più
nobile di tutto il dì, e la più vertuosa.”[438]

[438] “The sixth hour, that is, the middle of the day, is the most noble of all the day, and the most virtuous.” ------------------------------------------------------------------------

This means the whole of the sixth hour (as we should say, from 11 to 12 o’clock): the beginning of the seventh hour is the exact moment of noon, after which the day begins to decline. It was for this reason, Dante believes, that Christ chose to die during the sixth hour,[439] and during his 34th year, for then the day and his human life were both at their culmination, and had not begun to decline.

------------------------------------------------------------------------ [439] _Luke_ xxiii. 44-46. Dante understands this to mean that death took place at about the sixth hour, not the ninth. ------------------------------------------------------------------------

There was some difference in the methods of reckoning the hours for Church offices, but Dante tells in this same passage which of them he considered right, and he follows it consistently in his works. The Church day was divided into four parts, viz.:—

At the equinox=
Tierce, Sunrise to the end of the third hour 6 to 9 a.m.
Sext, Fourth to end of sixth hour 9 a.m. to 12 noon
Nones, Seventh to end of ninth 12 noon to 3 p.m.
Vespers, Tenth hour to sunset 3 to 6 p.m.

Two of the Church offices were to be said at the beginning, and one at the end, of these periods, as follows:—

Tierce, at the end _i.e._ 9 a.m. at the equinox.
Nones, at the beginning _i.e._ 12 noon.
Vespers, ” ” _i.e._ 3 p.m. at the equinox.

Thus sext is omitted altogether, and Dante says that the reason for the arrangement is to approximate in every case to that hour which is the noblest of the whole day, the sixth.

Mid-tierce was halfway through the period from sunrise to the end of the third hour, that is, 7.30 a.m. at the time of the equinox; and mid-nones and mid-vespers were counted in the same way.

As an instance of reckoning hours by the sun, we may quote the reply of Adam when Dante desired to know how long time he had spent in Eden:

“Dalla prim’ ora a quella che seconda,
Come il sol muta quadra, l’ora sesta.”[440]

------------------------------------------------------------------------
[440]
“From the first hour to that which cometh next
(As the sun changes quarter) to the sixth.”
_Par._ xxvi. 141-142. (_Carey_).
------------------------------------------------------------------------

Just as the time of day may be told, if one is accustomed to watch the sun, by noting how much of the daily course has been run, so the time of day or night (according to her phase) may be told by the moon; only with her we must take into consideration the rapid and variable motion eastwards in the zodiac. Alfraganus says that her _mean_ daily motion in longitude is 13° and nearly 11 minutes,[441] but that a small amount must be added or subtracted every day in order to find her true motion. As a clock, therefore, for use in daily life, she leaves much to be desired. This daily motion makes her fall constantly behind the sun, so that she loses time every day, and not even the same amount of time; for though she crosses the meridian on an average 50½ minutes later each day, the interval is sometimes only 38 minutes and sometimes as much as 66 minutes. And her times of setting and rising are even more variable.

------------------------------------------------------------------------ [441] It is easily seen that this is correct, if we divide the 360° of the moon’s path through the zodiac by the 27 days and eight hours in which she traverses it, and returns to the same star. Brunetto Latini says “La lune s’esloigne _dou Soleil_ chascun jor xiii degrez po s’en faut,” but he is wrong, having apparently forgotten that the sun is also moving in the same direction, at the average rate of nearly 1° daily. ------------------------------------------------------------------------

This is easily understood if we remember how much the sun’s time of setting varies throughout the year, according to the part of the zodiac in which he is travelling, and consider that what the sun does in a year the moon does in a month. And in her case the effect is sometimes exaggerated, sometimes diminished, for her path in the zodiac is inclined to the sun’s path; moreover, her greatest departure from it to north and south takes place in different parts of the zodiac at different times. These facts were well known to Ptolemy and to mediæval astronomers, and everyone who watches the moon must have noticed how variable are the intervals between one moonrise or one moonset and the next.

The extent of variability also depends upon our latitude (just as with sunrises and sunsets); and in Florence the retardation in one day may sometimes be only twenty minutes, sometimes an hour and twenty minutes. The difference would be less in Dante’s Purgatory, since this was in latitude 32° south, and the intervals between moonset and moonset become less variable in length as we approach the equator, just as the days become less unequal all the year round. Still, they would vary a good deal, so we must conclude that Dante only means to indicate the time quite roughly when he uses the moon as a clock. As a matter of fact, he seldom does so in the _Divine Comedy_ without giving us another clue to the time as well.

These passages all belong to a most interesting series of time indications, which we may now proceed to examine.

_VI. DANTE’S JOURNEY THROUGH THE THREE REALMS: INDICATIONS OF TIME AND DIRECTION BY MEANS OF THE SKIES._

1. TIME REFERENCES IN THE DIVINE COMEDY.

The plan of the universe through which Dante feigns himself to have journeyed is familiar to all readers of the _Divine Comedy_. Hell, as the Fathers taught, was a subterranean cavity, and Dante pictures it as an inverted cone, whose apex reaches the exact centre of Earth and therefore of the universe. It is situated vertically underneath Jerusalem, the centre of the inhabited Earth. He departs from the Fathers, however, in removing Purgatory from these dim regions, and placing it on an island in the midst of the ocean of the uninhabited hemisphere, exactly at the antipodes of Jerusalem. On this island rises a mountain whose immensely lofty summit reaches the upper regions of the atmosphere, and upon the summit is the Eden of our first parents. This original conception is an extraordinary gain, both from the artistic and the allegorical points of view; and it is in harmony with the idea of Aristotle, and of many mediæval writers, that the southern hemisphere was the “nobler” part of Earth. Here, then, man was permitted to dwell before the Fall, and hither come repentant souls, saved from Hell, but not yet pure enough to enter Heaven. Paradise consists of all the spheres of mediæval astronomy, and the poet rises from one to another until he finally reaches the all-embracing Empyrean, where his vision ends.

Nowhere does he describe this scheme in full, but it was evidently clear in his own mind, and by following him step by step in his journey it is easily reconstructed, and is represented in the accompanying diagram.

In the same way he never states how long a time he spent on this visionary journey, yet this also he had definitely determined, and in each Cantica he refers once to the period of time alloted to each realm.

In the last Circle but one of the Inferno, he is warned by Virgil that the time allowed is drawing to a close;[442] in the last but one of the Purgatorio Virgil urges him to make the best use of the time appointed;[443] and in the Paradiso, just before the final vision, St. Bernard tells him that the time of his trance is nearly over.[444]

------------------------------------------------------------------------ [442] _Inf._ xxix. 11.

[443] _Purg._ xxiii. 5, 6.

[444] _Par._ xxxii. 139. ------------------------------------------------------------------------

In the first Canto, which is introductory to the whole _Commedia_, he mentions the time at which he assumes that his vision began. It was “nel mezzo del cammin di nostra vita,”[445] which may mean simply that he was middle-aged, or comparing it with the passage in the _Convivio_ quoted earlier (see p. 347), we may suppose it to mean that he was exactly in his 35th year. The season was spring—“la dolce stagione,”[446] and when night was over the sun rose among those stars which were with him at the Creation, which was believed to have taken place at the vernal equinox some sixty-five centuries before.

------------------------------------------------------------------------ [445] “Midway in the journey of our life.” _Inf._ i. 1.

[446] “The sweet season.” _Inf._ i. 43.

“Il Sol montava su con quelle stelle
Ch’ eran con lui quando l’Amor Divino
Mosse da prima quelle cose belle.”[447]

[447]
“Aloft the sun ascended with those stars
That with him rose when Love Divine first moved
Those its fair works.”
_Inf._ i. 38-40. (_Carey_).
------------------------------------------------------------------------

The expression “quelle stelle,”[448] however, shows us that Dante does not intend to be pedantically accurate, which would indeed be inartistic in a poem. He speaks several times of the supposed slow motion of the star sphere,[449] and although he never mentions its effect in shifting the place of the equinox continually among the stars, we can hardly imagine that he failed to understand this. He knew quite well, therefore, that the stars which accompanied the sun in that first springtime of the world could not be the same stars which rose with him now. But astronomers had agreed to call the part of the sky which contains the vernal equinox by its old name, and it would be exceedingly tiresome if he were to distinguish, every time he mentioned them, between the zodiacal constellations and the zodiacal signs; there shall be no occasion, therefore, to stop and consider which he means, and no ambiguity: he assumes once for all that they always have been and always are identical, that the “first point of Aries” or vernal equinox is now and always at the beginning of the constellation Aries. To this assumption he is consistent throughout.

------------------------------------------------------------------------ [448] “Those stars.”

[449] _Purg._ xi. 108; _Conv._ II. xv. 12-14. ------------------------------------------------------------------------

Another important point to notice is that, since it is the time of the equinox, there is no difference between “temporary” and “equal” hours.[450] Days and nights are of equal length; sunrise and sunset are nearly at 6 a.m. and 6 p.m., according to our modern method of reckoning.[451] In this way also, and without any sacrifice of astronomical accuracy, the poet has simplified his time references for his readers.

------------------------------------------------------------------------ [450] _Conv._ III. vi. 28-30.

[451] On the day of the spring equinox the sun rises and sets a few minutes after six o’clock, because we set our clocks not by the real sun but the more convenient “mean sun.” ------------------------------------------------------------------------

We must observe, however, that the day is as uncertain as the year; for, although it is certainly near the equinox, “quelle stelle” may mean exactly the first point of Aries or only the constellation Aries in general. From this Canto alone, therefore, we cannot be sure of the exact date.