Dr. Moore thinks the authority better for a different reading, viz. “Dal mezzo”[329] instead of “Dell’ aer.”[330] In this case, we must take “mezzo puro” to mean mid-heaven, that is the zenith, “puro” being used as a noun, and meaning a cloudless sky (like “sereno” in Purg. v. 38); and “il sereno aspetto” must mean “the quiet scene.”
Venus appears again in the Purgatorio, shining upon the Mountain from the east before sunrise; and this time she is called Cytherea, after the island near which she was fabled to have risen from the sea, and in which she received a special worship.
“Dell’ oriente ... raggiò nel monte Citerea, Che di foco d’amor par sempre ardente.”[331]
The position of Venus in her course through the zodiac is indicated in the previous passage by the expression “velando i Pesci.”[332] The oscillating motion, by which she appears first on the morning and then on the evening side of the sun is referred to several times. In prose Dante speaks of her two apparitions, the morning and the evening: “la sua apparenza, or da mane, or da sera;”[333] in poetry, he describes her as wooing the sun, first following and then facing him:—
“la stella Che il sol vagheggia or da coppa or da ciglio.”[334]
Mercury and Venus (called rather oddly after their mothers), are said both to move closely round the sun:—
... “vidi com’ si move Circa e vicino a lui Maia e Dione.”[335]
“Quel bel pianeta di Mercuro”[336] keeps closest, for he is more hidden than any other in the rays of the sun. Here again the fact is expressed in simple prose in the Convivio:—
“Mercurio ... più va velata de’ raggi del sole che null’ altra stella.”[337]
which explains (if necessary) the more poetical language of the Paradiso:—