Sources : Cornica

Thomas of Cantimpré [circa 1200-1272 CE] (Liber de natura rerum, Birds 5.33): The cornica, as Pliny says, is the largest bird in the East. Although this bird is large, it does not have many feathers according to the size of its body. ... And this is the reason: Not every bird has a bladder, and the excess of water which it drinks passes into its feathers; the surplus of this bird's drink does not pass into the feathers, but - as is believed - into the lungs, of which the bird itself has large, fleshy, bloody, and similar to the lungs that are in a cow. - [Badke translation/paraphrase]