[451] _Feed Acheron, etc._: The idea of this image is taken from the figure in Nebuchadnezzar's dream in Daniel ii. But here, instead of the Four Empires, the materials of the statue represent the Four Ages of the world; the foot of clay on which it stands being the present time, which is so bad that even iron were too good to represent it. Time turns his back to the outworn civilisations of the East, and his face to Rome, which, as the seat of the Empire and the Church, holds the secret of the future. The tears of time shed by every Age save that of Gold feed the four infernal streams and pools of Acheron, Styx, Phlegethon, and Cocytus. Line 117 indicates that these are all fed by the same water; are in fact different names for the same flood of tears. The reason why Dante has not hitherto observed the connection between them is that he has not made a complete circuit of each or indeed of any circle, as Virgil reminds him at line 124, etc. The rivulet by which they stand drains the boiling Phlegethon--where the water is all changed to blood, because in it the murderers are punished--and flowing through the forest of the suicides and the desert of the blasphemers, etc., tumbles into the Eighth Circle as described in Canto xvi. 103. Cocytus they are afterward to reach. An objection to this account of the infernal rivers as being all fed by the same waters may be found in the difference of volume of the great river of Acheron (_Inf._ iii. 71) and of this brooklet. But this difference is perhaps to be explained by the evaporation from the boiling waters of Phlegethon and of this stream which drains it. Dante is almost the only poet applied to whom such criticism would not be trifling. Another difficult point is how Cocytus should not in time have filled, and more than filled, the Ninth Circle. [452] _To the left hand_: Twice only as they descend they turn their course to the right hand (_Inf._ ix. 132, and xvii. 31). The circuit of the Inferno they do not complete till they reach the very base. [453] _Lethe_: Found in the Earthly Paradise, as described in _Purgatorio_ xxviii. 130. CANTO XV.