Assertion: feather's structure | /r/CapableOf | trap air
Facets:
Source sentences:
text: Down’ is the undercoating of waterfowl (goose, duck or swan) and consists of light, fluffy filaments growing from a central quill point, thereby creating a three dimensional structure which traps air and gives down insulating ability.
text: Down, the undercoating of waterfowl including geese, ducks and swans, is the light, fluffy filaments that grow from a central quill point, making a structure that captures air and gives it insulating ability.