Note 1 — CANTO XXVIII.
Charles Eliot Norton translation
The innumerable sparks each moved in accord with the gyration of its flaming circle. The doubling of the chess alludes to the story that the inventor of the game asked, as his reward from the King of Persia, a grain of wheat for the first square of the board, two for the second, and so on to the last or sixty-fourth square. The number reached by this process of duplication extends to twenty figures.