Lastly, he mentions the discovery that the moon comes between us and the sun, which we have learned from eclipses, as an example of the proper method of reasoning: for we must first ask whether a thing is, and afterwards why it is. Thus man’s wonder leads him to knowledge.[370]
The eclipsed moon is only once mentioned, viz. in De Mon. III. iv. 140-142, where she is described as not wholly dark. With his usual indifference to her Dante fails to note the often extraordinary beauty of her colouring when the eclipse is total.
7. COMETS AND METEORS.
The connection between these two classes of heavenly bodies seems to be real, though its exact nature is still a mystery. In old days little or no distinction was drawn between them, so that it is sometimes difficult to know whether a writer is describing a large meteor, or a comet, or a shower of falling stars.
Dante only mentions comets once, very briefly, when he describes spirits in Paradise as “fiammando forte a guisa di comete.”[371] He says nothing of the magnificent comet described by Ristoro, which rose at three o’clock in the morning, huge as a mountain, and with great rays like a mane; but travelling always towards the south grew gradually fainter, and disappeared after 60 days. Yet it was seen in Tuscany shortly before Dante’s birth, and it was thought to herald the death of the Pope (Urban IV. in 1264) and the terrible war in which first Manfred and afterwards Conradin were slain. These events are familiar to every reader of the Divine Comedy,[372] but there is never any mention of the comet.
Nor does he describe in any detail the fiery cross which was seen in the sky above Florence “in the beginning of her destruction,” which does not mean, as one might think, the legendary sack of the city by Totila, but the treacherous entry of Charles of Valois, “Totila secundus,”[373] in November 1301. This portent was of course considered as of ill omen for the Republic, and although Dante was still absent on his embassy to Rome, and cannot have seen it himself, it is rather remarkable that he says so little about it. It is described by an eye-witness, “Io, che chiaramente la viddi”[374] as a red cross which appeared in the evening over the Priors’ Palace; the vertical arm seemed to be 20 ells long, the transverse one a little shorter, and it remained visible for as long as it would take a horse to gallop two furlongs. Villani the historian describes it as like a comet with an immense trail, as of smoke, behind it. Dante merely mentions it, together with the ball of fire seen by Seneca at the death of Augustus, which, judging by Seneca’s own words, was also a large meteor, for he describes it as flashing into sight and moving very rapidly, disappearing as it moved.[375]
Dante calls meteors “kindled vapours,”[376] in accordance with the doctrines of Aristotle, but the popular idea of them is shown by his observation that they might be taken for stars in motion, only that no star vanishes from its place, and they are only seen for a short time.[377] Ristoro d’Arezzo had already alluded to this fallacy:—
“Alquanti non savi credono ch’elle sieno stelle, che caggino del cielo e vengano meno.”[378]
He gives the same reason as Dante for disbelieving this, and Seneca had expressed it more forcibly, saying that if true there would be no more stars in the sky, for some meteors are seen every night.
Albertus Magnus, who seems to have had a genius for mistaking his authorities, quotes Alfraganus as stating that shooting stars are most frequent in evening twilight, though nothing of the kind is said in the Elementa. Dante perhaps accepted the statement, though it is by no means necessarily implied in his “di prima notte:”[379] moreover there is some authority for the alternative reading of “mezza notte.”[380] Wherever the idea originated, its sole foundation must have been the circumstance that more persons are awake in the early than in the late hours of the night: the fact is that more meteorites are captured by the morning side of the earth, which is turned in the direction towards which she is moving in her orbit.