Note 620 — CANTO XXIII.
James Romanes Sibbald translation
His heaving throat: In Purgatory Dante is known for a mortal by his casting a shadow. Here he is known to be of flesh and blood by the act of respiration; yet, as appears from line 113, the shades, too, breathe as well as perform other functions of living bodies. At least they seem so to do, but this is all only in appearance. They only seem to be flesh and blood, having no weight, casting no shadow, and drawing breath in a way of their own. Dante, as has been said (Inf. vi. 36), is hard put to it to make them subject to corporal pains and yet be only shadows.