Note 513 — CANTO XVII.
James Romanes Sibbald translation
A terrific roar: Of the water falling to the ground. On beginning the descent they had left the waterfall on the left hand, but Geryon, after fetching one or more great circles, passes in front of it, and then they have it on the right. There is no further mention of the waters of Phlegethon till they are found frozen in Cocytus (Inf. xxxii. 23). Philalethes suggests that they flow under the Eighth Circle.