Apparently if you close your eyes…
Water is never silent when it moves. Brooks babble, streams burble, and a larger, slower river has deeper, more complicated things to say. Great rivers speak at low frequencies, too low for human ears to hear, too low even for dogs’ ears to pick up their words; and the River of Time told its tales at the lowest frequencies of all, and only elephants’ ears could listen to its songs. However, the Elephant Birds’ eyes were shut. Elephant eyes are small and dry and don’t see very far at all. Eyesight would be of no use in the search for the River of Time.
From a description of the Elephant Birds in the magical adventure Luka and the Fire of Life by Salman Rushdie.
And so for day 823