Accident to my large machine, 138 Action of aeroplanes and power required, 100 Adjustment of birds’ wings, 19 Admiralty specification for a steamship, 48 Advantages of driving aeroplanes on to new air, 140 Advantages and disadvantages of very narrow planes, 143 Aeroplanes:-- Action of, 31, 32, 100 Advantageous angle of, 139 Advantages and disadvantages of very narrow, 143 „ arising from driving aeroplanes on to new air, 140 Curvature of, 145 Evolution of a wide aeroplane, 102 Experiments with, 49-59 Fabric covered, 131 Lifting effect of, 141 Lifting surface of, 103 Philipps’ sustainers, 146 Reduction of projected horizontal area, 3, 4 Shape and efficiency of, 99 Superposed, 144, 146 Testing fabrics for, 50 The paradox aeroplane, 88 Air currents and the flight of birds, 11 „ Conclusions regarding, 21 „ Alpes Maritimes, 17 „ Mediterranean, 18 „ Mid-Atlantic, 16 „ 2,000 feet above the earth’s surface, 22 „ witnessed at Cadiz, 20 Angles and degrees compared, 115 Antoinette motor, The, 89