v. 71.  Save one.] “Except that principle of rarity and denseness which thou hast assigned.”  By “formal principles, “principj formali, are meant constituent or essential causes.”  Milton, in imitation of this passage, introduces the angel arguing with Adam respecting the causes of the spots on the moon.

But, as a late French translator of the Paradise well remarks, his reasoning is physical; that of Dante partly metaphysical and partly theologic.

v. 111.  Within the heaven.] According to our Poet’s system, there are ten heavens; the seven planets, the eighth spheres containing the fixed stars, the primum mobile, and the empyrean.

v. 143.  The virtue mingled.] Virg.  Aen. 1. vi 724.  Principio coelum, &c.

CANTO III

v. 16.  Delusion.] “An error the contrary to that of Narcissus, because he mistook a shadow for a substance, I a substance for a shadow.”

v. 50.  Piccarda.] The sister of Forese whom we have seen in the Purgatory, Canto XXIII.

v. 90.  The Lady.] St. Clare, the foundress of the order called after her She was born of opulent and noble parents at Assisi, in 1193, and died in 1253.  See Biogr.  Univ. t. 1. p. 598. 8vo.  Paris, 1813.

v. 121.  Constance.] Daughter of Ruggieri, king of Sicily, who, being taken by force out of a monastery where she had professed, was married to the Emperor Henry Vl. and by him was mother to Frederick 11.  She was fifty years old or more at the time, and “because it was not credited that she could have a child at that age, she was delivered in a pavilion and it was given out, that any lady, who pleased, was at liberty to see her.  Many came, and saw her, and the suspicion ceased.”  Ricordano Malaspina in Muratori, Rer.  It.  Script. t. viii. p. 939; and G. Villani, in the same words, Hist.  I v. c. 16

The French translator above mentored speaks of her having poisoned her husband.  The death of Henry Vl. is recorded in the Chronicon Siciliae, by an anonymous writer, (Muratori, t. x.) but not a word of his having been poisoned by Constance, and Ricordano Malaspina even mentions her decease as happening before that of her husband, Henry V., for so this author, with some others, terms him. v. 122.  The second.] Henry Vl. son of Frederick I was the second emperor of the house of Saab; and his son Frederick ii “the third and last.”

CANTO IV

v. 6.  Between two deer]

Tigris ut auditis, diversa valle duorum
Extimulata fame, mugitibus armentorum
Neseit utro potius ruat, et ruere ardet utroque. 
Ovid, Metam. 1. v. 166

v. 13.  Daniel.] See Daniel, c. ii.

v. 24.  Plato.] [Greek here] Plato Timaeus v. ix. p. 326.  Edit.  Bip.  “The Creator, when he had framed the universe, distributed to the stars an equal number of souls, appointing to each soul its several star.”