During the past year considerable advance has been made on the question of Aeronautics relating to flying arrangements heavier than air (exclusive of balloons). I have always maintained that the power required for bird life has been much over-estimated. Take, for example, the flight of the pelican, which I have often witnessed. A dead bird weighed 21 lbs., with an extent of wings of 10 feet from end to end, speed 70 strokes per minute, each stroke averaging about one foot. It is evident that during a period of gliding flight with motionless wings these sustain the whole weight of the bird. The exertion or force will be during the oscilating or downstroke of the wing against this pressure.