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]).
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]
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.”
(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]
(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]
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.