But when the tilted plank let slide its freight into the sea, a second strange human murmur was heard, blended now with another inarticulate sound proceeding from certain larger sea-fowl, whose attention having been attracted by the peculiar commotion in the water resulting from the heavy sloped dive of the shotted hammock into the sea, flew screaming to the spot. So near the hull did they come, that the stridor or bony creak of their gaunt double-jointed pinions was audible.
Source: wiktionary