National Geographic : 1954 Apr
2. Lifting Pinions to the Fullest, He Takes Off on the Downbeat, Legs Extended 4. Approaching the Second Perch, He Lets Down Legs. 6. Feathers Pivot to Let Air Through the Wings. Tail Fans Out as a Brake © Kodachromes by Bernard Corby and Hance Roy Ivor Springy Legs Absorb Landing Shock lens 22 inches distant, and he had to allow for the interval between the brain's command and the finger's response on the button. The slightest miscalculation ruined a film. To the casual eye, the pictures seem to show a single bird. Actually the author used two of his bluebirds, Little Blue and Bonnie, Jr., to save both from fatigue and from gorging on too many tidbit rewards (next page). He chose the bluebirds because their plumage was almost identical. A leg band readily identifies Bonnie.