Feather barbs, coloured scanning electron micrograph (SEM). A feather is formed by rows of barbs (white, two partially seen here), which project from

---

Feather barbs, coloured scanning electron micrograph (SEM). A feather is formed by rows of barbs (white, two partially seen here), which project from either side of a central shaft (rachis, not seen). Each barb has rows of minute filaments called barbules (pink and purple). The barbules on one side bear hooks, while those on the other have a groove, hooking adjacent barbs together (hooking area can be seen down centre). This makes the feather strong, yet flexible and light, which is ideal for flight.

---

Size: 5100px × 3543px
Photo credit: © DR PHILIPPA UWINS, WHISTLER RESEARCH PTY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 1600s, 1675, 17th, adult, air, apparatus, artwork, boyle, british, caucasian, century, chemist, coloured, denis, discussing, engraving, equipment, europe, european, experiment, french, historical, history, human, illustration, inventor, inventors, irish, kingdom, laboratory, machine, male, man, men, middle-aged, papin, people, person, physical, physicist, physics, pioneer, pump, pumps, robert, science, scientist, scientists, surname, talking, technological, technology, uk, united, vacuum, vacuums, white